Enable sending MessagePorts to a different renderer (Blink side)

public/web/WebDOMMessageEvent.h

Index: public/web/WebDOMMessageEvent.h
diff --git a/public/web/WebDOMMessageEvent.h b/public/web/WebDOMMessageEvent.h
index 4f383382c60ecf845c00337404672340139d7c66..782d512d452abaf3de2424b049cfbb2496198974 100644
--- a/public/web/WebDOMMessageEvent.h
+++ b/public/web/WebDOMMessageEvent.h
@@ -47,11 +47,13 @@ class WebString;
 class WebDOMMessageEvent : public WebDOMEvent {
 public:
     WebDOMMessageEvent() { }
-    BLINK_EXPORT void initMessageEvent(const WebString& type, bool canBubble, bool cancelable, const WebSerializedScriptValue& messageData, const WebString& origin, const WebFrame* sourceFrame, const WebString& lastEventId);
+    BLINK_EXPORT void initMessageEvent(const WebString& type, bool canBubble, bool cancelable, const WebSerializedScriptValue& messageData, const WebString& origin, const WebFrame* sourceFrame, const WebString& lastEventId, const WebMessagePortChannelArray& channels = WebMessagePortChannelArray());
 
     BLINK_EXPORT WebSerializedScriptValue data() const;
     BLINK_EXPORT WebString origin() const;
 
+    BLINK_EXPORT WebMessagePortChannelArray releaseChannels();
+
 #if BLINK_IMPLEMENTATION
     explicit WebDOMMessageEvent(const WTF::PassRefPtr<WebCore::MessageEvent>& e) : WebDOMEvent(e) { }
 #endif