diff --git a/BUILD.gn b/BUILD.gn
index ef01067c90..12dce90be7 100644
--- a/BUILD.gn
+++ b/BUILD.gn
@@ -2861,12 +2861,12 @@ v8_component("v8_libplatform") {
     "include/libplatform/libplatform-export.h",
     "include/libplatform/libplatform.h",
     "include/libplatform/v8-tracing.h",
-    "src/libplatform/default-background-task-runner.cc",
-    "src/libplatform/default-background-task-runner.h",
     "src/libplatform/default-foreground-task-runner.cc",
     "src/libplatform/default-foreground-task-runner.h",
     "src/libplatform/default-platform.cc",
     "src/libplatform/default-platform.h",
+    "src/libplatform/default-worker-threads-task-runner.cc",
+    "src/libplatform/default-worker-threads-task-runner.h",
     "src/libplatform/task-queue.cc",
     "src/libplatform/task-queue.h",
     "src/libplatform/tracing/trace-buffer.cc",
diff --git a/include/v8-platform.h b/include/v8-platform.h
index bb463a8578..80e51aedc0 100644
--- a/include/v8-platform.h
+++ b/include/v8-platform.h
@@ -363,8 +363,7 @@ class Platform {
    * thread the task will be run on.
    */
   V8_DEPRECATE_SOON(
-      "ExpectedRuntime is deprecated, use CallOnWorkerThread(Task*) "
-      "instead.",
+      "ExpectedRuntime is deprecated, use CallOnWorkerThread() instead.",
       virtual void CallOnBackgroundThread(Task* task,
                                           ExpectedRuntime expected_runtime)) {
     // An implementation needs to be provided here because this is called by the
@@ -381,17 +380,18 @@ class Platform {
    * TODO(gab): Make pure virtual when all embedders override this instead of
    * CallOnBackgroundThread().
    */
-  virtual void CallOnWorkerThread(Task* task) {
-    CallOnBackgroundThread(task, kShortRunningTask);
+  virtual void CallOnWorkerThread(std::unique_ptr<Task> task) {
+    CallOnBackgroundThread(task.release(), kShortRunningTask);
   }
 
   /**
    * Schedules a task that blocks the main thread to be invoked with
    * high-priority on a worker thread.
    */
-  virtual void CallBlockingTaskOnWorkerThread(Task* task) {
-    // TODO(gab): Make pure-virtual when all embedders override this.
-    CallOnWorkerThread(task);
+  virtual void CallBlockingTaskOnWorkerThread(std::unique_ptr<Task> task) {
+    // Embedders may optionally override this to process these tasks in a high
+    // priority pool.
+    CallOnWorkerThread(std::move(task));
   }
 
   /**
diff --git a/src/compiler-dispatcher/compiler-dispatcher.cc b/src/compiler-dispatcher/compiler-dispatcher.cc
index 0331b3e9b1..24817aea0e 100644
--- a/src/compiler-dispatcher/compiler-dispatcher.cc
+++ b/src/compiler-dispatcher/compiler-dispatcher.cc
@@ -7,6 +7,7 @@
 #include "include/v8-platform.h"
 #include "include/v8.h"
 #include "src/base/platform/time.h"
+#include "src/base/template-utils.h"
 #include "src/cancelable-task.h"
 #include "src/compilation-info.h"
 #include "src/compiler-dispatcher/compiler-dispatcher-job.h"
@@ -123,11 +124,11 @@ void CompilerDispatcher::AbortTask::RunInternal() {
   dispatcher_->AbortInactiveJobs();
 }
 
-class CompilerDispatcher::BackgroundTask : public CancelableTask {
+class CompilerDispatcher::WorkerTask : public CancelableTask {
  public:
-  BackgroundTask(Isolate* isolate, CancelableTaskManager* task_manager,
-                 CompilerDispatcher* dispatcher);
-  ~BackgroundTask() override;
+  WorkerTask(Isolate* isolate, CancelableTaskManager* task_manager,
+             CompilerDispatcher* dispatcher);
+  ~WorkerTask() override;
 
   // CancelableTask implementation.
   void RunInternal() override;
@@ -135,17 +136,17 @@ class CompilerDispatcher::BackgroundTask : public CancelableTask {
  private:
   CompilerDispatcher* dispatcher_;
 
-  DISALLOW_COPY_AND_ASSIGN(BackgroundTask);
+  DISALLOW_COPY_AND_ASSIGN(WorkerTask);
 };
 
-CompilerDispatcher::BackgroundTask::BackgroundTask(
-    Isolate* isolate, CancelableTaskManager* task_manager,
-    CompilerDispatcher* dispatcher)
+CompilerDispatcher::WorkerTask::WorkerTask(Isolate* isolate,
+                                           CancelableTaskManager* task_manager,
+                                           CompilerDispatcher* dispatcher)
     : CancelableTask(task_manager), dispatcher_(dispatcher) {}
 
-CompilerDispatcher::BackgroundTask::~BackgroundTask() {}
+CompilerDispatcher::WorkerTask::~WorkerTask() {}
 
-void CompilerDispatcher::BackgroundTask::RunInternal() {
+void CompilerDispatcher::WorkerTask::RunInternal() {
   dispatcher_->DoBackgroundWork();
 }
 
@@ -188,7 +189,7 @@ CompilerDispatcher::CompilerDispatcher(Isolate* isolate, Platform* platform,
       memory_pressure_level_(MemoryPressureLevel::kNone),
       abort_(false),
       idle_task_scheduled_(false),
-      num_background_tasks_(0),
+      num_worker_tasks_(0),
       main_thread_blocking_on_job_(nullptr),
       block_for_testing_(false),
       semaphore_for_testing_(0) {
@@ -434,7 +435,7 @@ void CompilerDispatcher::AbortInactiveJobs() {
   }
   if (jobs_.empty()) {
     base::LockGuard<base::Mutex> lock(&mutex_);
-    if (num_background_tasks_ == 0) abort_ = false;
+    if (num_worker_tasks_ == 0) abort_ = false;
   }
 }
 
@@ -511,22 +512,22 @@ void CompilerDispatcher::ConsiderJobForBackgroundProcessing(
     base::LockGuard<base::Mutex> lock(&mutex_);
     pending_background_jobs_.insert(job);
   }
-  ScheduleMoreBackgroundTasksIfNeeded();
+  ScheduleMoreWorkerTasksIfNeeded();
 }
 
-void CompilerDispatcher::ScheduleMoreBackgroundTasksIfNeeded() {
+void CompilerDispatcher::ScheduleMoreWorkerTasksIfNeeded() {
   TRACE_EVENT0(TRACE_DISABLED_BY_DEFAULT("v8.compile"),
-               "V8.CompilerDispatcherScheduleMoreBackgroundTasksIfNeeded");
+               "V8.CompilerDispatcherScheduleMoreWorkerTasksIfNeeded");
   {
     base::LockGuard<base::Mutex> lock(&mutex_);
     if (pending_background_jobs_.empty()) return;
-    if (platform_->NumberOfWorkerThreads() <= num_background_tasks_) {
+    if (platform_->NumberOfWorkerThreads() <= num_worker_tasks_) {
       return;
     }
-    ++num_background_tasks_;
+    ++num_worker_tasks_;
   }
   platform_->CallOnWorkerThread(
-      new BackgroundTask(isolate_, task_manager_.get(), this));
+      base::make_unique<WorkerTask>(isolate_, task_manager_.get(), this));
 }
 
 void CompilerDispatcher::DoBackgroundWork() {
@@ -570,7 +571,7 @@ void CompilerDispatcher::DoBackgroundWork() {
 
   {
     base::LockGuard<base::Mutex> lock(&mutex_);
-    --num_background_tasks_;
+    --num_worker_tasks_;
 
     if (running_background_jobs_.empty() && abort_) {
       // This is the last background job that finished. The abort task
@@ -718,7 +719,7 @@ CompilerDispatcher::JobMap::const_iterator CompilerDispatcher::RemoveJob(
   it = jobs_.erase(it);
   if (jobs_.empty()) {
     base::LockGuard<base::Mutex> lock(&mutex_);
-    if (num_background_tasks_ == 0) abort_ = false;
+    if (num_worker_tasks_ == 0) abort_ = false;
   }
   return it;
 }
diff --git a/src/compiler-dispatcher/compiler-dispatcher.h b/src/compiler-dispatcher/compiler-dispatcher.h
index 2e1c961335..d7b2dc802f 100644
--- a/src/compiler-dispatcher/compiler-dispatcher.h
+++ b/src/compiler-dispatcher/compiler-dispatcher.h
@@ -117,16 +117,16 @@ class V8_EXPORT_PRIVATE CompilerDispatcher {
   FRIEND_TEST(CompilerDispatcherTest, EnqueueAndStepParsed);
   FRIEND_TEST(CompilerDispatcherTest, IdleTaskSmallIdleTime);
   FRIEND_TEST(CompilerDispatcherTest, CompileOnBackgroundThread);
-  FRIEND_TEST(CompilerDispatcherTest, FinishNowWithBackgroundTask);
-  FRIEND_TEST(CompilerDispatcherTest, AsyncAbortAllPendingBackgroundTask);
-  FRIEND_TEST(CompilerDispatcherTest, AsyncAbortAllRunningBackgroundTask);
+  FRIEND_TEST(CompilerDispatcherTest, FinishNowWithWorkerTask);
+  FRIEND_TEST(CompilerDispatcherTest, AsyncAbortAllPendingWorkerTask);
+  FRIEND_TEST(CompilerDispatcherTest, AsyncAbortAllRunningWorkerTask);
   FRIEND_TEST(CompilerDispatcherTest, FinishNowDuringAbortAll);
   FRIEND_TEST(CompilerDispatcherTest, CompileMultipleOnBackgroundThread);
 
   typedef std::map<JobId, std::unique_ptr<CompilerDispatcherJob>> JobMap;
   typedef IdentityMap<JobId, FreeStoreAllocationPolicy> SharedToJobIdMap;
   class AbortTask;
-  class BackgroundTask;
+  class WorkerTask;
   class IdleTask;
 
   void WaitForJobIfRunningOnBackground(CompilerDispatcherJob* job);
@@ -135,7 +135,7 @@ class V8_EXPORT_PRIVATE CompilerDispatcher {
   bool CanEnqueue(Handle<SharedFunctionInfo> function);
   JobMap::const_iterator GetJobFor(Handle<SharedFunctionInfo> shared) const;
   void ConsiderJobForBackgroundProcessing(CompilerDispatcherJob* job);
-  void ScheduleMoreBackgroundTasksIfNeeded();
+  void ScheduleMoreWorkerTasksIfNeeded();
   void ScheduleIdleTaskFromAnyThread();
   void ScheduleIdleTaskIfNeeded();
   void ScheduleAbortTask();
@@ -183,8 +183,8 @@ class V8_EXPORT_PRIVATE CompilerDispatcher {
 
   bool idle_task_scheduled_;
 
-  // Number of scheduled or running BackgroundTask objects.
-  int num_background_tasks_;
+  // Number of scheduled or running WorkerTask objects.
+  int num_worker_tasks_;
 
   // The set of CompilerDispatcherJobs that can be advanced on any thread.
   std::unordered_set<CompilerDispatcherJob*> pending_background_jobs_;
diff --git a/src/compiler-dispatcher/optimizing-compile-dispatcher.cc b/src/compiler-dispatcher/optimizing-compile-dispatcher.cc
index 89b1998241..36b063ff55 100644
--- a/src/compiler-dispatcher/optimizing-compile-dispatcher.cc
+++ b/src/compiler-dispatcher/optimizing-compile-dispatcher.cc
@@ -5,6 +5,7 @@
 #include "src/compiler-dispatcher/optimizing-compile-dispatcher.h"
 
 #include "src/base/atomicops.h"
+#include "src/base/template-utils.h"
 #include "src/cancelable-task.h"
 #include "src/compilation-info.h"
 #include "src/compiler.h"
@@ -225,14 +226,14 @@ void OptimizingCompileDispatcher::QueueForOptimization(CompilationJob* job) {
     blocked_jobs_++;
   } else {
     V8::GetCurrentPlatform()->CallOnWorkerThread(
-        new CompileTask(isolate_, this));
+        base::make_unique<CompileTask>(isolate_, this));
   }
 }
 
 void OptimizingCompileDispatcher::Unblock() {
   while (blocked_jobs_ > 0) {
     V8::GetCurrentPlatform()->CallOnWorkerThread(
-        new CompileTask(isolate_, this));
+        base::make_unique<CompileTask>(isolate_, this));
     blocked_jobs_--;
   }
 }
diff --git a/src/d8.cc b/src/d8.cc
index d59350039c..6da8862327 100644
--- a/src/d8.cc
+++ b/src/d8.cc
@@ -191,11 +191,10 @@ class PredictablePlatform : public Platform {
     return platform_->GetForegroundTaskRunner(isolate);
   }
 
-  void CallOnWorkerThread(Task* task) override {
+  void CallOnWorkerThread(std::unique_ptr<Task> task) override {
     // It's not defined when background tasks are being executed, so we can just
     // execute them right away.
     task->Run();
-    delete task;
   }
 
   void CallOnForegroundThread(v8::Isolate* isolate, Task* task) override {
diff --git a/src/heap/array-buffer-collector.cc b/src/heap/array-buffer-collector.cc
index 88b798d098..412e4ad05a 100644
--- a/src/heap/array-buffer-collector.cc
+++ b/src/heap/array-buffer-collector.cc
@@ -4,6 +4,7 @@
 
 #include "src/heap/array-buffer-collector.h"
 
+#include "src/base/template-utils.h"
 #include "src/heap/array-buffer-tracker.h"
 #include "src/heap/heap-inl.h"
 
@@ -48,8 +49,8 @@ class ArrayBufferCollector::FreeingTask final : public CancelableTask {
 void ArrayBufferCollector::FreeAllocationsOnBackgroundThread() {
   heap_->account_external_memory_concurrently_freed();
   if (!heap_->IsTearingDown() && FLAG_concurrent_array_buffer_freeing) {
-    FreeingTask* task = new FreeingTask(heap_);
-    V8::GetCurrentPlatform()->CallOnWorkerThread(task);
+    V8::GetCurrentPlatform()->CallOnWorkerThread(
+        base::make_unique<FreeingTask>(heap_));
   } else {
     // Fallback for when concurrency is disabled/restricted.
     FreeAllocations();
diff --git a/src/heap/concurrent-marking.cc b/src/heap/concurrent-marking.cc
index 6022e441f8..6fdbb659e6 100644
--- a/src/heap/concurrent-marking.cc
+++ b/src/heap/concurrent-marking.cc
@@ -8,6 +8,7 @@
 #include <unordered_map>
 
 #include "include/v8config.h"
+#include "src/base/template-utils.h"
 #include "src/heap/gc-tracer.h"
 #include "src/heap/heap-inl.h"
 #include "src/heap/heap.h"
@@ -612,9 +613,10 @@ void ConcurrentMarking::ScheduleTasks() {
       task_state_[i].preemption_request.SetValue(false);
       is_pending_[i] = true;
       ++pending_task_count_;
-      Task* task = new Task(heap_->isolate(), this, &task_state_[i], i);
+      auto task =
+          base::make_unique<Task>(heap_->isolate(), this, &task_state_[i], i);
       cancelable_id_[i] = task->id();
-      V8::GetCurrentPlatform()->CallOnWorkerThread(task);
+      V8::GetCurrentPlatform()->CallOnWorkerThread(std::move(task));
     }
   }
   DCHECK_EQ(task_count_, pending_task_count_);
diff --git a/src/heap/item-parallel-job.cc b/src/heap/item-parallel-job.cc
index f101db4041..e909ef69d7 100644
--- a/src/heap/item-parallel-job.cc
+++ b/src/heap/item-parallel-job.cc
@@ -90,10 +90,11 @@ void ItemParallelJob::Run(std::shared_ptr<Counters> async_counters) {
                                     : 0;
   CancelableTaskManager::Id* task_ids =
       new CancelableTaskManager::Id[num_tasks];
-  Task* main_task = nullptr;
+  std::unique_ptr<Task> main_task;
   for (size_t i = 0, start_index = 0; i < num_tasks;
        i++, start_index += items_per_task + (i < items_remainder ? 1 : 0)) {
-    Task* task = tasks_[i];
+    auto task = std::move(tasks_[i]);
+    DCHECK(task);
 
     // By definition there are less |items_remainder| to distribute then
     // there are tasks processing items so this cannot overflow while we are
@@ -105,15 +106,15 @@ void ItemParallelJob::Run(std::shared_ptr<Counters> async_counters) {
                               : base::Optional<AsyncTimedHistogram>());
     task_ids[i] = task->id();
     if (i > 0) {
-      V8::GetCurrentPlatform()->CallBlockingTaskOnWorkerThread(task);
+      V8::GetCurrentPlatform()->CallBlockingTaskOnWorkerThread(std::move(task));
     } else {
-      main_task = task;
+      main_task = std::move(task);
     }
   }
 
   // Contribute on main thread.
+  DCHECK(main_task);
   main_task->Run();
-  delete main_task;
 
   // Wait for background tasks.
   for (size_t i = 0; i < num_tasks; i++) {
diff --git a/src/heap/item-parallel-job.h b/src/heap/item-parallel-job.h
index 4c21f69ca9..51e0afd401 100644
--- a/src/heap/item-parallel-job.h
+++ b/src/heap/item-parallel-job.h
@@ -126,7 +126,7 @@ class V8_EXPORT_PRIVATE ItemParallelJob {
   ~ItemParallelJob();
 
   // Adds a task to the job. Transfers ownership to the job.
-  void AddTask(Task* task) { tasks_.push_back(task); }
+  void AddTask(Task* task) { tasks_.push_back(std::unique_ptr<Task>(task)); }
 
   // Adds an item to the job. Transfers ownership to the job.
   void AddItem(Item* item) { items_.push_back(item); }
@@ -140,7 +140,7 @@ class V8_EXPORT_PRIVATE ItemParallelJob {
 
  private:
   std::vector<Item*> items_;
-  std::vector<Task*> tasks_;
+  std::vector<std::unique_ptr<Task>> tasks_;
   CancelableTaskManager* cancelable_task_manager_;
   base::Semaphore* pending_tasks_;
   DISALLOW_COPY_AND_ASSIGN(ItemParallelJob);
diff --git a/src/heap/spaces.cc b/src/heap/spaces.cc
index b0552a992d..ecbffb35e4 100644
--- a/src/heap/spaces.cc
+++ b/src/heap/spaces.cc
@@ -9,6 +9,7 @@
 #include "src/base/bits.h"
 #include "src/base/macros.h"
 #include "src/base/platform/semaphore.h"
+#include "src/base/template-utils.h"
 #include "src/counters.h"
 #include "src/heap/array-buffer-tracker.h"
 #include "src/heap/concurrent-marking.h"
@@ -349,7 +350,7 @@ void MemoryAllocator::Unmapper::FreeQueuedChunks() {
       }
       return;
     }
-    UnmapFreeMemoryTask* task = new UnmapFreeMemoryTask(heap_->isolate(), this);
+    auto task = base::make_unique<UnmapFreeMemoryTask>(heap_->isolate(), this);
     if (FLAG_trace_unmapper) {
       PrintIsolate(heap_->isolate(),
                    "Unmapper::FreeQueuedChunks: new task id=%" PRIu64 "\n",
@@ -360,7 +361,7 @@ void MemoryAllocator::Unmapper::FreeQueuedChunks() {
     DCHECK_GE(active_unmapping_tasks_.Value(), 0);
     active_unmapping_tasks_.Increment(1);
     task_ids_[pending_unmapping_tasks_++] = task->id();
-    V8::GetCurrentPlatform()->CallOnWorkerThread(task);
+    V8::GetCurrentPlatform()->CallOnWorkerThread(std::move(task));
   } else {
     PerformFreeMemoryOnQueuedChunks<FreeMode::kUncommitPooled>();
   }
diff --git a/src/heap/store-buffer.cc b/src/heap/store-buffer.cc
index 17eff94a4f..3df5a5a53f 100644
--- a/src/heap/store-buffer.cc
+++ b/src/heap/store-buffer.cc
@@ -7,6 +7,7 @@
 #include <algorithm>
 
 #include "src/base/macros.h"
+#include "src/base/template-utils.h"
 #include "src/counters.h"
 #include "src/heap/incremental-marking.h"
 #include "src/isolate.h"
@@ -94,8 +95,8 @@ void StoreBuffer::FlipStoreBuffers() {
 
   if (!task_running_ && FLAG_concurrent_store_buffer) {
     task_running_ = true;
-    Task* task = new Task(heap_->isolate(), this);
-    V8::GetCurrentPlatform()->CallOnWorkerThread(task);
+    V8::GetCurrentPlatform()->CallOnWorkerThread(
+        base::make_unique<Task>(heap_->isolate(), this));
   }
 }
 
diff --git a/src/heap/sweeper.cc b/src/heap/sweeper.cc
index 3a70cecf4f..b2c4549389 100644
--- a/src/heap/sweeper.cc
+++ b/src/heap/sweeper.cc
@@ -4,6 +4,7 @@
 
 #include "src/heap/sweeper.h"
 
+#include "src/base/template-utils.h"
 #include "src/heap/array-buffer-tracker-inl.h"
 #include "src/heap/gc-tracer.h"
 #include "src/heap/mark-compact-inl.h"
@@ -154,12 +155,12 @@ void Sweeper::StartSweeperTasks() {
     ForAllSweepingSpaces([this](AllocationSpace space) {
       DCHECK(IsValidSweepingSpace(space));
       num_sweeping_tasks_.Increment(1);
-      SweeperTask* task = new SweeperTask(heap_->isolate(), this,
-                                          &pending_sweeper_tasks_semaphore_,
-                                          &num_sweeping_tasks_, space);
+      auto task = base::make_unique<SweeperTask>(
+          heap_->isolate(), this, &pending_sweeper_tasks_semaphore_,
+          &num_sweeping_tasks_, space);
       DCHECK_LT(num_tasks_, kMaxSweeperTasks);
       task_ids_[num_tasks_++] = task->id();
-      V8::GetCurrentPlatform()->CallOnWorkerThread(task);
+      V8::GetCurrentPlatform()->CallOnWorkerThread(std::move(task));
     });
     ScheduleIncrementalSweepingTask();
   }
@@ -551,11 +552,11 @@ void Sweeper::StartIterabilityTasks() {
 
   DCHECK(!iterability_task_started_);
   if (FLAG_concurrent_sweeping && !iterability_list_.empty()) {
-    IterabilityTask* task = new IterabilityTask(heap_->isolate(), this,
-                                                &iterability_task_semaphore_);
+    auto task = base::make_unique<IterabilityTask>(
+        heap_->isolate(), this, &iterability_task_semaphore_);
     iterability_task_id_ = task->id();
     iterability_task_started_ = true;
-    V8::GetCurrentPlatform()->CallOnWorkerThread(task);
+    V8::GetCurrentPlatform()->CallOnWorkerThread(std::move(task));
   }
 }
 
diff --git a/src/libplatform/default-platform.cc b/src/libplatform/default-platform.cc
index 8f7337a9dc..74975e71fa 100644
--- a/src/libplatform/default-platform.cc
+++ b/src/libplatform/default-platform.cc
@@ -14,8 +14,8 @@
 #include "src/base/platform/platform.h"
 #include "src/base/platform/time.h"
 #include "src/base/sys-info.h"
-#include "src/libplatform/default-background-task-runner.h"
 #include "src/libplatform/default-foreground-task-runner.h"
+#include "src/libplatform/default-worker-threads-task-runner.h"
 
 namespace v8 {
 namespace platform {
@@ -96,7 +96,7 @@ DefaultPlatform::DefaultPlatform(
 
 DefaultPlatform::~DefaultPlatform() {
   base::LockGuard<base::Mutex> guard(&lock_);
-  if (background_task_runner_) background_task_runner_->Terminate();
+  if (worker_threads_task_runner_) worker_threads_task_runner_->Terminate();
   for (auto it : foreground_task_runner_map_) {
     it.second->Terminate();
   }
@@ -114,9 +114,9 @@ void DefaultPlatform::SetThreadPoolSize(int thread_pool_size) {
 
 void DefaultPlatform::EnsureBackgroundTaskRunnerInitialized() {
   base::LockGuard<base::Mutex> guard(&lock_);
-  if (!background_task_runner_) {
-    background_task_runner_ =
-        std::make_shared<DefaultBackgroundTaskRunner>(thread_pool_size_);
+  if (!worker_threads_task_runner_) {
+    worker_threads_task_runner_ =
+        std::make_shared<DefaultWorkerThreadsTaskRunner>(thread_pool_size_);
   }
 }
 
@@ -196,11 +196,11 @@ std::shared_ptr<TaskRunner> DefaultPlatform::GetForegroundTaskRunner(
 std::shared_ptr<TaskRunner> DefaultPlatform::GetWorkerThreadsTaskRunner(
     v8::Isolate*) {
   EnsureBackgroundTaskRunnerInitialized();
-  return background_task_runner_;
+  return worker_threads_task_runner_;
 }
 
-void DefaultPlatform::CallOnWorkerThread(Task* task) {
-  GetWorkerThreadsTaskRunner(nullptr)->PostTask(std::unique_ptr<Task>(task));
+void DefaultPlatform::CallOnWorkerThread(std::unique_ptr<Task> task) {
+  GetWorkerThreadsTaskRunner(nullptr)->PostTask(std::move(task));
 }
 
 void DefaultPlatform::CallOnForegroundThread(v8::Isolate* isolate, Task* task) {
diff --git a/src/libplatform/default-platform.h b/src/libplatform/default-platform.h
index ab2aa60fce..77a7a86586 100644
--- a/src/libplatform/default-platform.h
+++ b/src/libplatform/default-platform.h
@@ -26,7 +26,7 @@ namespace platform {
 class Thread;
 class WorkerThread;
 class DefaultForegroundTaskRunner;
-class DefaultBackgroundTaskRunner;
+class DefaultWorkerThreadsTaskRunner;
 class DefaultPageAllocator;
 
 class V8_PLATFORM_EXPORT DefaultPlatform : public NON_EXPORTED_BASE(Platform) {
@@ -60,7 +60,7 @@ class V8_PLATFORM_EXPORT DefaultPlatform : public NON_EXPORTED_BASE(Platform) {
       v8::Isolate* isolate) override;
   std::shared_ptr<TaskRunner> GetWorkerThreadsTaskRunner(
       v8::Isolate* isolate) override;
-  void CallOnWorkerThread(Task* task) override;
+  void CallOnWorkerThread(std::unique_ptr<Task> task) override;
   void CallOnForegroundThread(v8::Isolate* isolate, Task* task) override;
   void CallDelayedOnForegroundThread(Isolate* isolate, Task* task,
                                      double delay_in_seconds) override;
@@ -78,7 +78,7 @@ class V8_PLATFORM_EXPORT DefaultPlatform : public NON_EXPORTED_BASE(Platform) {
   base::Mutex lock_;
   int thread_pool_size_;
   IdleTaskSupport idle_task_support_;
-  std::shared_ptr<DefaultBackgroundTaskRunner> background_task_runner_;
+  std::shared_ptr<DefaultWorkerThreadsTaskRunner> worker_threads_task_runner_;
   std::map<v8::Isolate*, std::shared_ptr<DefaultForegroundTaskRunner>>
       foreground_task_runner_map_;
 
diff --git a/src/libplatform/default-background-task-runner.cc b/src/libplatform/default-worker-threads-task-runner.cc
similarity index 59%
rename from src/libplatform/default-background-task-runner.cc
rename to src/libplatform/default-worker-threads-task-runner.cc
index b556b6c3fe..bc2ebbd015 100644
--- a/src/libplatform/default-background-task-runner.cc
+++ b/src/libplatform/default-worker-threads-task-runner.cc
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#include "src/libplatform/default-background-task-runner.h"
+#include "src/libplatform/default-worker-threads-task-runner.h"
 
 #include "src/base/platform/mutex.h"
 #include "src/libplatform/worker-thread.h"
@@ -10,19 +10,19 @@
 namespace v8 {
 namespace platform {
 
-DefaultBackgroundTaskRunner::DefaultBackgroundTaskRunner(
+DefaultWorkerThreadsTaskRunner::DefaultWorkerThreadsTaskRunner(
     uint32_t thread_pool_size) {
   for (uint32_t i = 0; i < thread_pool_size; ++i) {
     thread_pool_.push_back(base::make_unique<WorkerThread>(&queue_));
   }
 }
 
-DefaultBackgroundTaskRunner::~DefaultBackgroundTaskRunner() {
+DefaultWorkerThreadsTaskRunner::~DefaultWorkerThreadsTaskRunner() {
   // This destructor is needed because we have unique_ptr to the WorkerThreads,
   // und the {WorkerThread} class is forward declared in the header file.
 }
 
-void DefaultBackgroundTaskRunner::Terminate() {
+void DefaultWorkerThreadsTaskRunner::Terminate() {
   base::LockGuard<base::Mutex> guard(&lock_);
   terminated_ = true;
   queue_.Terminate();
@@ -30,28 +30,29 @@ void DefaultBackgroundTaskRunner::Terminate() {
   thread_pool_.clear();
 }
 
-void DefaultBackgroundTaskRunner::PostTask(std::unique_ptr<Task> task) {
+void DefaultWorkerThreadsTaskRunner::PostTask(std::unique_ptr<Task> task) {
   base::LockGuard<base::Mutex> guard(&lock_);
   if (terminated_) return;
   queue_.Append(std::move(task));
 }
 
-void DefaultBackgroundTaskRunner::PostDelayedTask(std::unique_ptr<Task> task,
-                                                  double delay_in_seconds) {
+void DefaultWorkerThreadsTaskRunner::PostDelayedTask(std::unique_ptr<Task> task,
+                                                     double delay_in_seconds) {
   base::LockGuard<base::Mutex> guard(&lock_);
   if (terminated_) return;
-  // There is no use case for this function on a background thread at the
+  // There is no use case for this function on a worker thread at the
   // moment, but it is still part of the interface.
   UNIMPLEMENTED();
 }
 
-void DefaultBackgroundTaskRunner::PostIdleTask(std::unique_ptr<IdleTask> task) {
-  // There are no idle background tasks.
+void DefaultWorkerThreadsTaskRunner::PostIdleTask(
+    std::unique_ptr<IdleTask> task) {
+  // There are no idle worker tasks.
   UNREACHABLE();
 }
 
-bool DefaultBackgroundTaskRunner::IdleTasksEnabled() {
-  // There are no idle background tasks.
+bool DefaultWorkerThreadsTaskRunner::IdleTasksEnabled() {
+  // There are no idle worker tasks.
   return false;
 }
 
diff --git a/src/libplatform/default-background-task-runner.h b/src/libplatform/default-worker-threads-task-runner.h
similarity index 72%
rename from src/libplatform/default-background-task-runner.h
rename to src/libplatform/default-worker-threads-task-runner.h
index ce2f7efa05..5e46e3dd41 100644
--- a/src/libplatform/default-background-task-runner.h
+++ b/src/libplatform/default-worker-threads-task-runner.h
@@ -2,8 +2,8 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#ifndef V8_LIBPLATFORM_DEFAULT_BACKGROUND_TASK_RUNNER_H_
-#define V8_LIBPLATFORM_DEFAULT_BACKGROUND_TASK_RUNNER_H_
+#ifndef V8_LIBPLATFORM_DEFAULT_WORKER_THREADS_TASK_RUNNER_H_
+#define V8_LIBPLATFORM_DEFAULT_WORKER_THREADS_TASK_RUNNER_H_
 
 #include "include/v8-platform.h"
 #include "src/libplatform/task-queue.h"
@@ -14,12 +14,12 @@ namespace platform {
 class Thread;
 class WorkerThread;
 
-class V8_PLATFORM_EXPORT DefaultBackgroundTaskRunner
+class V8_PLATFORM_EXPORT DefaultWorkerThreadsTaskRunner
     : public NON_EXPORTED_BASE(TaskRunner) {
  public:
-  DefaultBackgroundTaskRunner(uint32_t thread_pool_size);
+  DefaultWorkerThreadsTaskRunner(uint32_t thread_pool_size);
 
-  ~DefaultBackgroundTaskRunner();
+  ~DefaultWorkerThreadsTaskRunner();
 
   void Terminate();
 
@@ -42,4 +42,4 @@ class V8_PLATFORM_EXPORT DefaultBackgroundTaskRunner
 
 }  // namespace platform
 }  // namespace v8
-#endif  // V8_LIBPLATFORM_DEFAULT_BACKGROUND_TASK_RUNNER_H_
+#endif  // V8_LIBPLATFORM_DEFAULT_WORKER_THREADS_TASK_RUNNER_H_
diff --git a/test/cctest/cctest.h b/test/cctest/cctest.h
index 50c4d06ae4..31f8ba9e39 100644
--- a/test/cctest/cctest.h
+++ b/test/cctest/cctest.h
@@ -690,8 +690,8 @@ class TestPlatform : public v8::Platform {
     return old_platform_->GetWorkerThreadsTaskRunner(isolate);
   }
 
-  void CallOnWorkerThread(v8::Task* task) override {
-    old_platform_->CallOnWorkerThread(task);
+  void CallOnWorkerThread(std::unique_ptr<v8::Task> task) override {
+    old_platform_->CallOnWorkerThread(std::move(task));
   }
 
   void CallOnForegroundThread(v8::Isolate* isolate, v8::Task* task) override {
diff --git a/test/cctest/heap/test-incremental-marking.cc b/test/cctest/heap/test-incremental-marking.cc
index b9b6325fd1..bbf630f0ba 100644
--- a/test/cctest/heap/test-incremental-marking.cc
+++ b/test/cctest/heap/test-incremental-marking.cc
@@ -40,8 +40,8 @@ class MockPlatform : public TestPlatform {
   virtual ~MockPlatform() {
     delete task_;
     i::V8::SetPlatformForTesting(old_platform_);
-    for (Task* task : worker_tasks_) {
-      old_platform_->CallOnWorkerThread(task);
+    for (auto& task : worker_tasks_) {
+      old_platform_->CallOnWorkerThread(std::move(task));
     }
     worker_tasks_.clear();
   }
@@ -50,8 +50,8 @@ class MockPlatform : public TestPlatform {
     task_ = task;
   }
 
-  void CallOnWorkerThread(Task* task) override {
-    worker_tasks_.push_back(task);
+  void CallOnWorkerThread(std::unique_ptr<Task> task) override {
+    worker_tasks_.push_back(std::move(task));
   }
 
   bool IdleTasksEnabled(v8::Isolate* isolate) override { return false; }
@@ -67,7 +67,7 @@ class MockPlatform : public TestPlatform {
 
  private:
   Task* task_;
-  std::vector<Task*> worker_tasks_;
+  std::vector<std::unique_ptr<Task>> worker_tasks_;
   v8::Platform* old_platform_;
 };
 
diff --git a/test/cctest/wasm/test-streaming-compilation.cc b/test/cctest/wasm/test-streaming-compilation.cc
index 665f5fc7df..6716ded40d 100644
--- a/test/cctest/wasm/test-streaming-compilation.cc
+++ b/test/cctest/wasm/test-streaming-compilation.cc
@@ -44,8 +44,8 @@ class MockPlatform final : public TestPlatform {
     task_runner_->PostTask(std::unique_ptr<Task>(task));
   }
 
-  void CallOnWorkerThread(v8::Task* task) override {
-    task_runner_->PostTask(std::unique_ptr<Task>(task));
+  void CallOnWorkerThread(std::unique_ptr<v8::Task> task) override {
+    task_runner_->PostTask(std::move(task));
   }
 
   bool IdleTasksEnabled(v8::Isolate* isolate) override { return false; }
diff --git a/test/unittests/api/isolate-unittest.cc b/test/unittests/api/isolate-unittest.cc
index be7a56383c..377ad83187 100644
--- a/test/unittests/api/isolate-unittest.cc
+++ b/test/unittests/api/isolate-unittest.cc
@@ -9,6 +9,7 @@
 #include "include/v8.h"
 #include "src/base/macros.h"
 #include "src/base/platform/semaphore.h"
+#include "src/base/template-utils.h"
 #include "src/execution.h"
 #include "src/isolate.h"
 #include "src/v8.h"
@@ -61,7 +62,7 @@ TEST_F(IsolateTest, MemoryPressureNotificationBackground) {
   base::Semaphore semaphore(0);
 
   internal::V8::GetCurrentPlatform()->CallOnWorkerThread(
-      new MemoryPressureTask(isolate(), &semaphore));
+      base::make_unique<MemoryPressureTask>(isolate(), &semaphore));
 
   semaphore.Wait();
 
diff --git a/test/unittests/compiler-dispatcher/compiler-dispatcher-unittest.cc b/test/unittests/compiler-dispatcher/compiler-dispatcher-unittest.cc
index 484cb347a0..31a5044e14 100644
--- a/test/unittests/compiler-dispatcher/compiler-dispatcher-unittest.cc
+++ b/test/unittests/compiler-dispatcher/compiler-dispatcher-unittest.cc
@@ -10,6 +10,7 @@
 #include "src/api.h"
 #include "src/ast/ast-value-factory.h"
 #include "src/base/platform/semaphore.h"
+#include "src/base/template-utils.h"
 #include "src/compiler-dispatcher/compiler-dispatcher-job.h"
 #include "src/compiler-dispatcher/compiler-dispatcher-tracer.h"
 #include "src/compiler-dispatcher/unoptimized-compile-job.h"
@@ -93,7 +94,7 @@ class MockPlatform : public v8::Platform {
   ~MockPlatform() override {
     base::LockGuard<base::Mutex> lock(&mutex_);
     EXPECT_TRUE(foreground_tasks_.empty());
-    EXPECT_TRUE(background_tasks_.empty());
+    EXPECT_TRUE(worker_tasks_.empty());
     EXPECT_TRUE(idle_task_ == nullptr);
   }
 
@@ -111,14 +112,14 @@ class MockPlatform : public v8::Platform {
     return std::make_shared<MockTaskRunner>(this, is_foreground_task_runner);
   }
 
-  void CallOnWorkerThread(Task* task) override {
+  void CallOnWorkerThread(std::unique_ptr<Task> task) override {
     base::LockGuard<base::Mutex> lock(&mutex_);
-    background_tasks_.push_back(task);
+    worker_tasks_.push_back(std::move(task));
   }
 
   void CallOnForegroundThread(v8::Isolate* isolate, Task* task) override {
     base::LockGuard<base::Mutex> lock(&mutex_);
-    foreground_tasks_.push_back(task);
+    foreground_tasks_.push_back(std::unique_ptr<Task>(task));
   }
 
   void CallDelayedOnForegroundThread(v8::Isolate* isolate, Task* task,
@@ -166,9 +167,9 @@ class MockPlatform : public v8::Platform {
     return idle_task_;
   }
 
-  bool BackgroundTasksPending() {
+  bool WorkerTasksPending() {
     base::LockGuard<base::Mutex> lock(&mutex_);
-    return !background_tasks_.empty();
+    return !worker_tasks_.empty();
   }
 
   bool ForegroundTasksPending() {
@@ -176,57 +177,54 @@ class MockPlatform : public v8::Platform {
     return !foreground_tasks_.empty();
   }
 
-  void RunBackgroundTasksAndBlock(Platform* platform) {
-    std::vector<Task*> tasks;
+  void RunWorkerTasksAndBlock(Platform* platform) {
+    std::vector<std::unique_ptr<Task>> tasks;
     {
       base::LockGuard<base::Mutex> lock(&mutex_);
-      tasks.swap(background_tasks_);
+      tasks.swap(worker_tasks_);
     }
-    platform->CallOnWorkerThread(new TaskWrapper(this, tasks, true));
+    platform->CallOnWorkerThread(
+        base::make_unique<TaskWrapper>(this, std::move(tasks), true));
     sem_.Wait();
   }
 
-  void RunBackgroundTasks(Platform* platform) {
-    std::vector<Task*> tasks;
+  void RunWorkerTasks(Platform* platform) {
+    std::vector<std::unique_ptr<Task>> tasks;
     {
       base::LockGuard<base::Mutex> lock(&mutex_);
-      tasks.swap(background_tasks_);
+      tasks.swap(worker_tasks_);
     }
-    platform->CallOnWorkerThread(new TaskWrapper(this, tasks, false));
+    platform->CallOnWorkerThread(
+        base::make_unique<TaskWrapper>(this, std::move(tasks), false));
   }
 
   void RunForegroundTasks() {
-    std::vector<Task*> tasks;
+    std::vector<std::unique_ptr<Task>> tasks;
     {
       base::LockGuard<base::Mutex> lock(&mutex_);
       tasks.swap(foreground_tasks_);
     }
     for (auto& task : tasks) {
       task->Run();
-      delete task;
+      // Reset |task| before running the next one.
+      task.reset();
     }
   }
 
-  void ClearBackgroundTasks() {
-    std::vector<Task*> tasks;
+  void ClearWorkerTasks() {
+    std::vector<std::unique_ptr<Task>> tasks;
     {
       base::LockGuard<base::Mutex> lock(&mutex_);
-      tasks.swap(background_tasks_);
-    }
-    for (auto& task : tasks) {
-      delete task;
+      tasks.swap(worker_tasks_);
     }
   }
 
   void ClearForegroundTasks() {
-    std::vector<Task*> tasks;
+    std::vector<std::unique_ptr<Task>> tasks;
     {
       base::LockGuard<base::Mutex> lock(&mutex_);
       tasks.swap(foreground_tasks_);
     }
-    for (auto& task : tasks) {
-      delete task;
-    }
   }
 
   void ClearIdleTask() {
@@ -239,22 +237,23 @@ class MockPlatform : public v8::Platform {
  private:
   class TaskWrapper : public Task {
    public:
-    TaskWrapper(MockPlatform* platform, const std::vector<Task*>& tasks,
-                bool signal)
-        : platform_(platform), tasks_(tasks), signal_(signal) {}
+    TaskWrapper(MockPlatform* platform,
+                std::vector<std::unique_ptr<Task>> tasks, bool signal)
+        : platform_(platform), tasks_(std::move(tasks)), signal_(signal) {}
     ~TaskWrapper() = default;
 
     void Run() override {
       for (auto& task : tasks_) {
         task->Run();
-        delete task;
+        // Reset |task| before running the next one.
+        task.reset();
       }
       if (signal_) platform_->sem_.Signal();
     }
 
    private:
     MockPlatform* platform_;
-    std::vector<Task*> tasks_;
+    std::vector<std::unique_ptr<Task>> tasks_;
     bool signal_;
 
     DISALLOW_COPY_AND_ASSIGN(TaskWrapper);
@@ -269,9 +268,9 @@ class MockPlatform : public v8::Platform {
     void PostTask(std::unique_ptr<v8::Task> task) override {
       base::LockGuard<base::Mutex> lock(&platform_->mutex_);
       if (is_foreground_task_runner_) {
-        platform_->foreground_tasks_.push_back(task.release());
+        platform_->foreground_tasks_.push_back(std::move(task));
       } else {
-        platform_->background_tasks_.push_back(task.release());
+        platform_->worker_tasks_.push_back(std::move(task));
       }
     }
 
@@ -304,8 +303,8 @@ class MockPlatform : public v8::Platform {
   base::Mutex mutex_;
 
   IdleTask* idle_task_;
-  std::vector<Task*> background_tasks_;
-  std::vector<Task*> foreground_tasks_;
+  std::vector<std::unique_ptr<Task>> worker_tasks_;
+  std::vector<std::unique_ptr<Task>> foreground_tasks_;
 
   base::Semaphore sem_;
 
@@ -383,7 +382,7 @@ TEST_F(CompilerDispatcherTest, FinishAllNow) {
     ASSERT_TRUE(shared[i]->is_compiled());
   }
   platform.ClearIdleTask();
-  platform.ClearBackgroundTasks();
+  platform.ClearWorkerTasks();
 }
 
 TEST_F(CompilerDispatcherTest, IdleTask) {
@@ -497,12 +496,12 @@ TEST_F(CompilerDispatcherTest, CompileOnBackgroundThread) {
   ASSERT_TRUE(dispatcher.IsEnqueued(shared));
   ASSERT_FALSE(shared->is_compiled());
   ASSERT_FALSE(platform.IdleTaskPending());
-  ASSERT_TRUE(platform.BackgroundTasksPending());
+  ASSERT_TRUE(platform.WorkerTasksPending());
 
-  platform.RunBackgroundTasksAndBlock(V8::GetCurrentPlatform());
+  platform.RunWorkerTasksAndBlock(V8::GetCurrentPlatform());
 
   ASSERT_TRUE(platform.IdleTaskPending());
-  ASSERT_FALSE(platform.BackgroundTasksPending());
+  ASSERT_FALSE(platform.WorkerTasksPending());
   ASSERT_EQ(UnoptimizedCompileJob::Status::kCompiled,
             dispatcher.jobs_.begin()->second->status());
 
@@ -514,7 +513,7 @@ TEST_F(CompilerDispatcherTest, CompileOnBackgroundThread) {
   ASSERT_FALSE(platform.IdleTaskPending());
 }
 
-TEST_F(CompilerDispatcherTest, FinishNowWithBackgroundTask) {
+TEST_F(CompilerDispatcherTest, FinishNowWithWorkerTask) {
   MockPlatform platform;
   CompilerDispatcher dispatcher(i_isolate(), &platform, FLAG_stack_size);
 
@@ -540,17 +539,17 @@ TEST_F(CompilerDispatcherTest, FinishNowWithBackgroundTask) {
   ASSERT_TRUE(dispatcher.IsEnqueued(shared));
   ASSERT_FALSE(shared->is_compiled());
   ASSERT_FALSE(platform.IdleTaskPending());
-  ASSERT_TRUE(platform.BackgroundTasksPending());
+  ASSERT_TRUE(platform.WorkerTasksPending());
 
   // This does not block, but races with the FinishNow() call below.
-  platform.RunBackgroundTasks(V8::GetCurrentPlatform());
+  platform.RunWorkerTasks(V8::GetCurrentPlatform());
 
   ASSERT_TRUE(dispatcher.FinishNow(shared));
   // Finishing removes the SFI from the queue.
   ASSERT_FALSE(dispatcher.IsEnqueued(shared));
   ASSERT_TRUE(shared->is_compiled());
   if (platform.IdleTaskPending()) platform.ClearIdleTask();
-  ASSERT_FALSE(platform.BackgroundTasksPending());
+  ASSERT_FALSE(platform.WorkerTasksPending());
 }
 
 TEST_F(CompilerDispatcherTest, IdleTaskMultipleJobs) {
@@ -608,7 +607,7 @@ TEST_F(CompilerDispatcherTest, FinishNowException) {
   platform.ClearIdleTask();
 }
 
-TEST_F(CompilerDispatcherTest, AsyncAbortAllPendingBackgroundTask) {
+TEST_F(CompilerDispatcherTest, AsyncAbortAllPendingWorkerTask) {
   MockPlatform platform;
   CompilerDispatcher dispatcher(i_isolate(), &platform, FLAG_stack_size);
 
@@ -634,7 +633,7 @@ TEST_F(CompilerDispatcherTest, AsyncAbortAllPendingBackgroundTask) {
   ASSERT_TRUE(dispatcher.IsEnqueued(shared));
   ASSERT_FALSE(shared->is_compiled());
   ASSERT_FALSE(platform.IdleTaskPending());
-  ASSERT_TRUE(platform.BackgroundTasksPending());
+  ASSERT_TRUE(platform.WorkerTasksPending());
 
   // The background task hasn't yet started, so we can just cancel it.
   dispatcher.AbortAll(BlockingBehavior::kDontBlock);
@@ -643,14 +642,14 @@ TEST_F(CompilerDispatcherTest, AsyncAbortAllPendingBackgroundTask) {
   ASSERT_FALSE(dispatcher.IsEnqueued(shared));
   ASSERT_FALSE(shared->is_compiled());
 
-  platform.RunBackgroundTasksAndBlock(V8::GetCurrentPlatform());
+  platform.RunWorkerTasksAndBlock(V8::GetCurrentPlatform());
 
   if (platform.IdleTaskPending()) platform.ClearIdleTask();
-  ASSERT_FALSE(platform.BackgroundTasksPending());
+  ASSERT_FALSE(platform.WorkerTasksPending());
   ASSERT_FALSE(platform.ForegroundTasksPending());
 }
 
-TEST_F(CompilerDispatcherTest, AsyncAbortAllRunningBackgroundTask) {
+TEST_F(CompilerDispatcherTest, AsyncAbortAllRunningWorkerTask) {
   MockPlatform platform;
   CompilerDispatcher dispatcher(i_isolate(), &platform, FLAG_stack_size);
 
@@ -680,11 +679,11 @@ TEST_F(CompilerDispatcherTest, AsyncAbortAllRunningBackgroundTask) {
   ASSERT_TRUE(dispatcher.IsEnqueued(shared1));
   ASSERT_FALSE(shared1->is_compiled());
   ASSERT_FALSE(platform.IdleTaskPending());
-  ASSERT_TRUE(platform.BackgroundTasksPending());
+  ASSERT_TRUE(platform.WorkerTasksPending());
 
   // Kick off background tasks and freeze them.
   dispatcher.block_for_testing_.SetValue(true);
-  platform.RunBackgroundTasks(V8::GetCurrentPlatform());
+  platform.RunWorkerTasks(V8::GetCurrentPlatform());
 
   // Busy loop until the background task started running.
   while (dispatcher.block_for_testing_.Value()) {
@@ -719,13 +718,13 @@ TEST_F(CompilerDispatcherTest, AsyncAbortAllRunningBackgroundTask) {
 
   ASSERT_TRUE(platform.IdleTaskPending());
   platform.RunIdleTask(5.0, 1.0);
-  ASSERT_FALSE(platform.BackgroundTasksPending());
+  ASSERT_FALSE(platform.WorkerTasksPending());
   ASSERT_FALSE(platform.ForegroundTasksPending());
 
   // Now it's possible to enqueue new functions again.
   ASSERT_TRUE(dispatcher.Enqueue(shared2));
   ASSERT_TRUE(platform.IdleTaskPending());
-  ASSERT_FALSE(platform.BackgroundTasksPending());
+  ASSERT_FALSE(platform.WorkerTasksPending());
   ASSERT_FALSE(platform.ForegroundTasksPending());
   platform.ClearIdleTask();
 }
@@ -756,11 +755,11 @@ TEST_F(CompilerDispatcherTest, FinishNowDuringAbortAll) {
   ASSERT_TRUE(dispatcher.IsEnqueued(shared));
   ASSERT_FALSE(shared->is_compiled());
   ASSERT_FALSE(platform.IdleTaskPending());
-  ASSERT_TRUE(platform.BackgroundTasksPending());
+  ASSERT_TRUE(platform.WorkerTasksPending());
 
   // Kick off background tasks and freeze them.
   dispatcher.block_for_testing_.SetValue(true);
-  platform.RunBackgroundTasks(V8::GetCurrentPlatform());
+  platform.RunWorkerTasks(V8::GetCurrentPlatform());
 
   // Busy loop until the background task started running.
   while (dispatcher.block_for_testing_.Value()) {
@@ -789,14 +788,14 @@ TEST_F(CompilerDispatcherTest, FinishNowDuringAbortAll) {
   // Busy wait for the background task to finish.
   for (;;) {
     base::LockGuard<base::Mutex> lock(&dispatcher.mutex_);
-    if (dispatcher.num_background_tasks_ == 0) {
+    if (dispatcher.num_worker_tasks_ == 0) {
       break;
     }
   }
 
   ASSERT_TRUE(platform.ForegroundTasksPending());
   ASSERT_TRUE(platform.IdleTaskPending());
-  ASSERT_FALSE(platform.BackgroundTasksPending());
+  ASSERT_FALSE(platform.WorkerTasksPending());
 
   platform.RunForegroundTasks();
   {
@@ -866,7 +865,8 @@ TEST_F(CompilerDispatcherTest, MemoryPressureFromBackground) {
   ASSERT_TRUE(dispatcher.Enqueue(shared));
   base::Semaphore sem(0);
   V8::GetCurrentPlatform()->CallOnWorkerThread(
-      new PressureNotificationTask(i_isolate(), &dispatcher, &sem));
+      base::make_unique<PressureNotificationTask>(i_isolate(), &dispatcher,
+                                                  &sem));
 
   sem.Wait();
 
@@ -901,7 +901,7 @@ TEST_F(CompilerDispatcherTest, EnqueueJob) {
 
   ASSERT_TRUE(platform.IdleTaskPending());
   platform.ClearIdleTask();
-  ASSERT_FALSE(platform.BackgroundTasksPending());
+  ASSERT_FALSE(platform.WorkerTasksPending());
 }
 
 TEST_F(CompilerDispatcherTest, EnqueueAndStep) {
@@ -921,8 +921,8 @@ TEST_F(CompilerDispatcherTest, EnqueueAndStep) {
 
   ASSERT_TRUE(platform.IdleTaskPending());
   platform.ClearIdleTask();
-  ASSERT_TRUE(platform.BackgroundTasksPending());
-  platform.ClearBackgroundTasks();
+  ASSERT_TRUE(platform.WorkerTasksPending());
+  platform.ClearWorkerTasks();
 }
 
 TEST_F(CompilerDispatcherTest, CompileLazyFinishesDispatcherJob) {
@@ -991,9 +991,9 @@ TEST_F(CompilerDispatcherTest, EnqueueAndStepTwice) {
             dispatcher.jobs_.begin()->second->status());
 
   ASSERT_TRUE(platform.IdleTaskPending());
-  ASSERT_TRUE(platform.BackgroundTasksPending());
+  ASSERT_TRUE(platform.WorkerTasksPending());
   platform.ClearIdleTask();
-  platform.ClearBackgroundTasks();
+  platform.ClearWorkerTasks();
 }
 
 TEST_F(CompilerDispatcherTest, CompileMultipleOnBackgroundThread) {
@@ -1033,12 +1033,12 @@ TEST_F(CompilerDispatcherTest, CompileMultipleOnBackgroundThread) {
   ASSERT_FALSE(shared1->is_compiled());
   ASSERT_FALSE(shared2->is_compiled());
   ASSERT_FALSE(platform.IdleTaskPending());
-  ASSERT_TRUE(platform.BackgroundTasksPending());
+  ASSERT_TRUE(platform.WorkerTasksPending());
 
-  platform.RunBackgroundTasksAndBlock(V8::GetCurrentPlatform());
+  platform.RunWorkerTasksAndBlock(V8::GetCurrentPlatform());
 
   ASSERT_TRUE(platform.IdleTaskPending());
-  ASSERT_FALSE(platform.BackgroundTasksPending());
+  ASSERT_FALSE(platform.WorkerTasksPending());
   ASSERT_EQ(dispatcher.jobs_.size(), 2u);
   ASSERT_EQ(UnoptimizedCompileJob::Status::kCompiled,
             dispatcher.jobs_.begin()->second->status());
diff --git a/test/unittests/compiler-dispatcher/unoptimized-compile-job-unittest.cc b/test/unittests/compiler-dispatcher/unoptimized-compile-job-unittest.cc
index fc1818f35e..6344d3806e 100644
--- a/test/unittests/compiler-dispatcher/unoptimized-compile-job-unittest.cc
+++ b/test/unittests/compiler-dispatcher/unoptimized-compile-job-unittest.cc
@@ -9,6 +9,7 @@
 #include "src/ast/ast.h"
 #include "src/ast/scopes.h"
 #include "src/base/platform/semaphore.h"
+#include "src/base/template-utils.h"
 #include "src/compiler-dispatcher/compiler-dispatcher-job.h"
 #include "src/compiler-dispatcher/compiler-dispatcher-tracer.h"
 #include "src/compiler-dispatcher/unoptimized-compile-job.h"
@@ -226,9 +227,9 @@ TEST_F(UnoptimizedCompileJobTest, CompileOnBackgroundThread) {
   ASSERT_FALSE(job->IsFailed());
 
   base::Semaphore semaphore(0);
-  CompileTask* background_task = new CompileTask(job.get(), &semaphore);
+  auto background_task = base::make_unique<CompileTask>(job.get(), &semaphore);
   ASSERT_JOB_STATUS(CompilerDispatcherJob::Status::kPrepared, job);
-  V8::GetCurrentPlatform()->CallOnWorkerThread(background_task);
+  V8::GetCurrentPlatform()->CallOnWorkerThread(std::move(background_task));
   semaphore.Wait();
   job->FinalizeOnMainThread(isolate());
   ASSERT_FALSE(job->IsFailed());