Start changing WebDOMMessageEvent for using target execution context.

Source/web/WebDOMMessageEvent.cpp

 /*
  * Copyright (C) 2011 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 19 matching lines @@
 
 #include "config.h"
 #include "public/web/WebDOMMessageEvent.h"
 
 #include "bindings/core/v8/SerializedScriptValue.h"
 #include "core/dom/Document.h"
 #include "core/dom/MessagePort.h"
 #include "core/events/MessageEvent.h"
 #include "core/frame/LocalDOMWindow.h"
 #include "public/platform/WebString.h"
+#include "public/web/WebDocument.h"
 #include "public/web/WebFrame.h"
 #include "public/web/WebSerializedScriptValue.h"
 #include "web/WebLocalFrameImpl.h"
 
 namespace blink {
 
+void WebDOMMessageEvent::initMessageEvent(const WebString& type, bool canBubble, bool cancelable, const WebSerializedScriptValue& messageData, const WebString& origin, const WebFrame* sourceFrame, const WebDocument& targetDocument, const WebString& lastEventId, const WebMessagePortChannelArray& webChannels)
+{
+    ASSERT(m_private.get());
+    ASSERT(isMessageEvent());
+    DOMWindow* window = nullptr;
+    if (sourceFrame)
+        window = toCoreFrame(sourceFrame)->domWindow();
+    RefPtrWillBeRawPtr<Document> coreDocument = PassRefPtrWillBeRawPtr<Document>(targetDocument);
+    MessagePortArray* ports = MessagePort::toMessagePortArray(coreDocument.get(), webChannels);
+    // Use an empty array for |ports| when it is null because this function
+    // is used to implement postMessage().
+    if (!ports)
+        ports = new MessagePortArray;
+    unwrap<MessageEvent>()->initMessageEvent(type, canBubble, cancelable, messageData, origin, lastEventId, window, ports);
+}
+
 void WebDOMMessageEvent::initMessageEvent(const WebString& type, bool canBubble, bool cancelable, const WebSerializedScriptValue& messageData, const WebString& origin, const WebFrame* sourceFrame, const WebString& lastEventId, const WebMessagePortChannelArray& webChannels)
 {
     ASSERT(m_private.get());

[dcheng, 2015/08/15 05:12:30]

Can we re-express this in terms of the new interface? Then it'll be clear
there's no difference between the old/new overloads.

[sgurun-gerrit only, 2015/08/18 15:17:30]

Done.

     ASSERT(isMessageEvent());
     DOMWindow* window = nullptr;
     // TODO(alexmos): Figure out if this is the right thing to do.
     if (sourceFrame)
         window = toCoreFrame(sourceFrame)->domWindow();
     MessagePortArray* ports = nullptr;
     // TODO(alexmos): make ports work properly with OOPIF.
     if (sourceFrame && sourceFrame->isWebLocalFrame())
         ports = MessagePort::toMessagePortArray(toLocalDOMWindow(window)->document(), webChannels);
     // Use an empty array for |ports| when it is null because this function
@@ skipping 18 matching lines @@
     MessagePortChannelArray* channels = constUnwrap<MessageEvent>()->channels();
     WebMessagePortChannelArray webChannels(channels ? channels->size() : 0);
     if (channels) {
         for (size_t i = 0; i < channels->size(); ++i)
             webChannels[i] = (*channels)[i].leakPtr();
     }
     return webChannels;
 }
 
 } // namespace blink