DOMDataStore should be cleared when shutting down worker threads

Source/bindings/v8/WorkerScriptController.cpp

 /*
  * Copyright (C) 2009, 2012 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:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 82 matching lines @@
 private:
     explicit IsolateCleanupTask(v8::Isolate* isolate) : m_isolate(isolate)  { }
 
     v8::Isolate* m_isolate;
 };
 
 WorkerScriptController::~WorkerScriptController()
 {
     ThreadState::current()->removeInterruptor(m_interruptor.get());
 
-    RELEASE_ASSERT(m_world->hasOneRef());
-    // ~DOMWrapperWorld() must be called before disposing the isolate.
-    m_world = nullptr;
-
     // The corresponding call to didStartWorkerRunLoop is in
     // WorkerThread::workerThread().
     // See http://webkit.org/b/83104#c14 for why this is here.
     blink::Platform::current()->didStopWorkerRunLoop(blink::WebWorkerRunLoop(&m_workerGlobalScope.thread()->runLoop()));
 
     disposeContext();
 
+    m_world->dispose();

[haraken, 2014/03/10 10:47:32]

I noticed that m_world->dispose() must be executed before
didStopWorkerRunLoop(). Otherwise, we crash a couple of IndexedDB tests
because...

- m_world->dispose() destructs IDBRequests.
- didStopWorkerRunLoop() destructs IndexedDBDispatcher.
- IDBRequests::deref() requires IndexedDBDispatcher.

I fixed the issue in the latest CL. Landing.

+
     ThreadState::current()->addCleanupTask(IsolateCleanupTask::create(m_isolate));
 }
 
 void WorkerScriptController::disposeContext()
 {
     m_perContextData.clear();
 }
 
 bool WorkerScriptController::initializeContextIfNeeded()
 {
     if (m_perContextData)
         return true;
 
     v8::Handle<v8::Context> context = v8::Context::New(m_isolate);
     if (context.IsEmpty())
         return false;
 
-    m_perContextData = V8PerContextData::create(context, m_world.get());
+    m_perContextData = V8PerContextData::create(context, m_world);
 
     v8::Context::Scope scope(context);
 
     // Set DebugId for the new context.
     context->SetEmbedderData(0, v8AtomicString(m_isolate, "worker"));
 
     // Create a new JS object and use it as the prototype for the shadow global object.
     const WrapperTypeInfo* contextType = &V8DedicatedWorkerGlobalScope::wrapperTypeInfo;
     if (m_workerGlobalScope.isServiceWorkerGlobalScope())
         contextType = &V8ServiceWorkerGlobalScope::wrapperTypeInfo;
@@ skipping 64 matching lines @@
 void WorkerScriptController::evaluate(const ScriptSourceCode& sourceCode, RefPtr<ErrorEvent>* errorEvent)
 {
     if (isExecutionForbidden())
         return;
 
     WorkerGlobalScopeExecutionState state;
     evaluate(sourceCode.source(), sourceCode.url().string(), sourceCode.startPosition(), &state);
     if (state.hadException) {
         if (errorEvent) {
             *errorEvent = m_workerGlobalScope.shouldSanitizeScriptError(state.sourceURL, NotSharableCrossOrigin) ?
-                ErrorEvent::createSanitizedError(nullptr) : ErrorEvent::create(state.errorMessage, state.sourceURL, state.lineNumber, state.columnNumber, nullptr);
+                ErrorEvent::createSanitizedError(0) : ErrorEvent::create(state.errorMessage, state.sourceURL, state.lineNumber, state.columnNumber, 0);
             V8ErrorHandler::storeExceptionOnErrorEventWrapper(errorEvent->get(), state.exception.v8Value(), m_isolate);
         } else {
             ASSERT(!m_workerGlobalScope.shouldSanitizeScriptError(state.sourceURL, NotSharableCrossOrigin));
-            RefPtr<ErrorEvent> event = m_errorEventFromImportedScript ? m_errorEventFromImportedScript.release() : ErrorEvent::create(state.errorMessage, state.sourceURL, state.lineNumber, state.columnNumber, nullptr);
+            RefPtr<ErrorEvent> event = m_errorEventFromImportedScript ? m_errorEventFromImportedScript.release() : ErrorEvent::create(state.errorMessage, state.sourceURL, state.lineNumber, state.columnNumber, 0);
             m_workerGlobalScope.reportException(event, nullptr, NotSharableCrossOrigin);
         }
     }
 }
 
 void WorkerScriptController::scheduleExecutionTermination()
 {
     // The mutex provides a memory barrier to ensure that once
     // termination is scheduled, isExecutionTerminating will
     // accurately reflect that state when called from another thread.
@@ skipping 42 matching lines @@
     v8::Handle<v8::Context> context = isolate->GetCurrentContext();
     v8::Handle<v8::Object> global = V8WorkerGlobalScope::findInstanceInPrototypeChain(context->Global(), isolate);
     // Return 0 if the current executing context is not the worker context.
     if (global.IsEmpty())
         return 0;
     WorkerGlobalScope* workerGlobalScope = V8WorkerGlobalScope::toNative(global);
     return workerGlobalScope->script();
 }
 
 } // namespace WebCore