Revert "Enable OneShot optimizations by default"

This reverts commit e938b7a3e5.

Reason for revert: Reverting because of gc-stress failures - https://ci.chromium.org/p/v8/builders/luci.v8.ci/V8%20Linux%20-%20gc%20stress/18299

Original change's description:
> Enable OneShot optimizations by default
> 
> BUG=v8:8072
> 
> Change-Id: I2068d66644628fe1de7a6be30b8d43ecfae04e93
> Reviewed-on: https://chromium-review.googlesource.com/1220047
> Commit-Queue: Chandan Reddy <chandanreddy@google.com>
> Reviewed-by: Camillo Bruni <cbruni@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#55875}

TBR=cbruni@chromium.org,chandanreddy@google.com

Change-Id: If3bfb5e142a873f534f831da413d26e78d2e3716
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: v8:8072
Reviewed-on: https://chromium-review.googlesource.com/1224481
Reviewed-by: Deepti Gandluri <gdeepti@chromium.org>
Commit-Queue: Deepti Gandluri <gdeepti@chromium.org>
Cr-Commit-Position: refs/heads/master@{#55876}

src/flag-definitions.h

@@ -324,7 +324,7 @@ DEFINE_BOOL(optimize_for_size, false,
             "speed")
 
 // Flag for one shot optimiztions.
-DEFINE_BOOL(enable_one_shot_optimization, true,
+DEFINE_BOOL(enable_one_shot_optimization, false,
             "Enable size optimizations for the code that will "
             "only be executed once")
 

test/cctest/test-api-accessors.cc

@@ -337,7 +337,6 @@ TEST(SetAccessorSetSideEffectReceiverCheck2) {
   LocalContext env;
   v8::Isolate* isolate = env->GetIsolate();
   v8::HandleScope scope(isolate);
-  i::FLAG_enable_one_shot_optimization = false;
 
   v8::Local<v8::FunctionTemplate> templ = v8::FunctionTemplate::New(
       isolate, ConstructCallback, v8::Local<v8::Value>(),

test/debugger/debug/side-effect/debug-evaluate-no-side-effect-runtime-check.js

@@ -2,8 +2,6 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-// Flags: --no-enable-one-shot-optimization
-
 Debug = debug.Debug;
 
 // StaCurrentContextSlot

test/debugger/debug/side-effect/debug-evaluate-no-side-effect.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: --no-enable-one-shot-optimization
 Debug = debug.Debug
 
 var exception = null;

test/mjsunit/regress/regress-crbug-380671.js

@@ -4,15 +4,11 @@
 
 // Flags: --mock-arraybuffer-allocator --expose-gc
 
-function test() {
-  var buffer = new ArrayBuffer(0xc0000000);
-  assertEquals(0xc0000000, buffer.byteLength);
-  // We call the GC here to free up the large array buffer. Otherwise, the
-  // mock allocator would allow us to allocate more than the physical memory
-  // available on 32bit platforms, leaving the internal counters in an invalid
-  // state.
-  buffer = null;
-  gc();
-}
-
-test();
+var buffer = new ArrayBuffer(0xc0000000);
+assertEquals(0xc0000000, buffer.byteLength);
+// We call the GC here to free up the large array buffer. Otherwise, the
+// mock allocator would allow us to allocate more than the physical memory
+// available on 32bit platforms, leaving the internal counters in an invalid
+// state.
+buffer = null;
+gc();