[debug-wrapper] Implement StepFrame through runtime

StepFrame is a combination of StepIn/StepOut, e.g. it breaks to the next
frame change. This is not part of the public API, but we want to keep it
for internal tests.

BUG=v8:5530

Review-Url: https://codereview.chromium.org/2514303003
Cr-Commit-Position: refs/heads/master@{#41177}

src/runtime/runtime-debug.cc

@@ -1240,6 +1240,18 @@ RUNTIME_FUNCTION(Runtime_PrepareStep) {
   return isolate->heap()->undefined_value();
 }
 
+RUNTIME_FUNCTION(Runtime_PrepareStepFrame) {
+  HandleScope scope(isolate);
+  DCHECK_EQ(0, args.length());
+  CHECK(isolate->debug()->CheckExecutionState());
+
+  // Clear all current stepping setup.
+  isolate->debug()->ClearStepping();
+
+  // Prepare step.
+  isolate->debug()->PrepareStep(StepFrame);
+  return isolate->heap()->undefined_value();
+}
 
 // Clear all stepping set by PrepareStep.
 RUNTIME_FUNCTION(Runtime_ClearStepping) {

src/runtime/runtime.h

@@ -169,6 +169,7 @@ namespace internal {
   F(ChangeBreakOnException, 2, 1)               \
   F(IsBreakOnException, 1, 1)                   \
   F(PrepareStep, 2, 1)                          \
+  F(PrepareStepFrame, 0, 1)                     \
   F(ClearStepping, 0, 1)                        \
   F(DebugEvaluate, 6, 1)                        \
   F(DebugEvaluateGlobal, 4, 1)                  \

test/debugger/debug/debug-stepframe-clearing.js

@@ -2,7 +2,6 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-// Flags: --expose-debug-as debug
 
 // This test ensures that IC learning doesn't interfere with stepping into
 // property accessor. f1()'s ICs are allowed to learn to a monomorphic state,

test/debugger/debug/debug-stepframe.js

@@ -2,7 +2,6 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-// Flags: --expose-debug-as debug
 
 function f0() {
   var v00 = 0;              // Break 1

test/debugger/test-api.js

@@ -378,6 +378,7 @@ class DebugWrapper {
       case this.StepAction.StepOut: this.stepOut(); break;
       case this.StepAction.StepNext: this.stepOver(); break;
       case this.StepAction.StepIn: this.stepInto(); break;
+      case this.StepAction.StepFrame: %PrepareStepFrame(); break;
       default: %AbortJS("Unsupported StepAction"); break;
     }
   }