[ABANDONED] Call Microtask::performCheckpoint for each worker task.

Source/bindings/v8/ScriptRegexp.cpp

 /*
  * Copyright (C) 2004, 2008, 2009 Apple Inc. All rights reserved.
  * Copyright (C) 2008 Collabora Ltd.
  * Copyright (C) 2011 Peter Varga (pvarga@webkit.org), University of Szeged
  * Copyright (C) 2013 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
@@ skipping 21 matching lines @@
 #include "bindings/v8/V8Binding.h"
 #include "bindings/v8/V8PerIsolateData.h"
 #include "bindings/v8/V8ScriptRunner.h"
 
 namespace WebCore {
 
 ScriptRegexp::ScriptRegexp(const String& pattern, TextCaseSensitivity caseSensitivity, MultilineMode multilineMode)
 {
     v8::Isolate* isolate = v8::Isolate::GetCurrent();
     v8::HandleScope handleScope(isolate);
-    v8::Context::Scope contextScope(V8PerIsolateData::from(isolate)->ensureDomInJSContext());
+    v8::Local<v8::Context> context = V8PerIsolateData::from(isolate)->ensureDomInJSContext();
+    if (context.IsEmpty()) {
+        // The script execution is terminated.
+        return;
+    }
+    v8::Context::Scope contextScope(context);
     v8::TryCatch tryCatch;
 
     unsigned flags = v8::RegExp::kNone;
     if (caseSensitivity == TextCaseInsensitive)
         flags |= v8::RegExp::kIgnoreCase;
     if (multilineMode == MultilineEnabled)
         flags |= v8::RegExp::kMultiline;
 
     v8::Local<v8::RegExp> regex = v8::RegExp::New(v8String(isolate, pattern), static_cast<v8::RegExp::Flags>(flags));
 
@@ skipping 38 matching lines @@
     int matchOffset = result->Get(v8AtomicString(isolate, "index"))->ToInt32()->Value();
     if (matchLength) {
         v8::Local<v8::String> match = result->Get(0).As<v8::String>();
         *matchLength = match->Length();
     }
 
     return matchOffset + startFrom;
 }
 
 } // namespace WebCore