SuspendableScriptExecutor executes code once

Source/web/SuspendableScriptExecutor.cpp

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "config.h"
 #include "web/SuspendableScriptExecutor.h"
 
 #include "bindings/core/v8/ScriptController.h"
 #include "bindings/core/v8/ScriptSourceCode.h"
 #include "core/dom/Document.h"
 #include "core/frame/LocalFrame.h"
 #include "platform/UserGestureIndicator.h"
 #include "public/platform/WebVector.h"
 #include "public/web/WebScriptExecutionCallback.h"
 
 namespace blink {
 
 void SuspendableScriptExecutor::createAndRun(LocalFrame* frame, int worldID, const WillBeHeapVector<ScriptSourceCode>& sources, int extensionGroup, bool userGesture, WebScriptExecutionCallback* callback)
 {
     RefPtrWillBeRawPtr<SuspendableScriptExecutor> executor = adoptRefWillBeNoop(new SuspendableScriptExecutor(frame, worldID, sources, extensionGroup, userGesture, callback));
     executor->ref();
     executor->run();
 }
 
 void SuspendableScriptExecutor::resume()
 {
-    executeAndDestroySelf();
+    if (!m_isStarted)

[pfeldman, 2015/02/04 12:45:20]

This implies that the code containing alert will affect the order of execution

...
alert()
  <--- resume will be fired here.
...

[kozy, 2015/02/04 13:12:33]

Fixed.

+        executeAndDestroySelf();
 }
 
 void SuspendableScriptExecutor::contextDestroyed()
 {
     // this method can only be called if the script was not called in run()
     // and context remained suspend (method resume has never called)
     ActiveDOMObject::contextDestroyed();
-    m_callback->completed(Vector<v8::Local<v8::Value>>());
-    deref();
+    if (!m_isStarted) {
+        m_callback->completed(Vector<v8::Local<v8::Value>>());
+        deref();
+    }
 }
 
 SuspendableScriptExecutor::SuspendableScriptExecutor(LocalFrame* frame, int worldID, const WillBeHeapVector<ScriptSourceCode>& sources, int extensionGroup, bool userGesture, WebScriptExecutionCallback* callback)
     : ActiveDOMObject(frame->document())
     , m_frame(frame)
     , m_worldID(worldID)
     , m_sources(sources)
     , m_extensionGroup(extensionGroup)
     , m_userGesture(userGesture)
+    , m_isStarted(false)
     , m_callback(callback)
 {
 }
 
 SuspendableScriptExecutor::~SuspendableScriptExecutor()
 {
 }
 
 void SuspendableScriptExecutor::run()
 {
     suspendIfNeeded();
     ExecutionContext* context = executionContext();
     ASSERT(context);
-    if (context && !context->activeDOMObjectsAreSuspended())
+    if (!m_isStarted && context && !context->activeDOMObjectsAreSuspended())
         executeAndDestroySelf();
 }
 
 void SuspendableScriptExecutor::executeAndDestroySelf()
 {
+    m_isStarted = true;
     // after calling the destructor of object - object will be unsubscribed from
     // resumed and contextDestroyed LifecycleObserver methods
     OwnPtr<UserGestureIndicator> indicator;
     if (m_userGesture)
         indicator = adoptPtr(new UserGestureIndicator(DefinitelyProcessingNewUserGesture));
 
     v8::HandleScope scope(v8::Isolate::GetCurrent());
     Vector<v8::Local<v8::Value>> results;
     if (m_worldID) {
         m_frame->script().executeScriptInIsolatedWorld(m_worldID, m_sources, m_extensionGroup, &results);
     } else {
         v8::Local<v8::Value> scriptValue = m_frame->script().executeScriptInMainWorldAndReturnValue(m_sources.first());
         results.append(scriptValue);
     }
     m_callback->completed(results);
     deref();
 }
 
 void SuspendableScriptExecutor::trace(Visitor* visitor)
 {
 #if ENABLE(OILPAN)
     visitor->trace(m_frame);
     visitor->trace(m_sources);
 #endif
     ActiveDOMObject::trace(visitor);
 }
 
 } // namespace blink