ServiceWorker: Add initial implementation of ExtendableMessageEvent behind a flag

third_party/WebKit/public/web/modules/serviceworker/WebServiceWorkerContextClient.h

Index: third_party/WebKit/public/web/modules/serviceworker/WebServiceWorkerContextClient.h
diff --git a/third_party/WebKit/public/web/modules/serviceworker/WebServiceWorkerContextClient.h b/third_party/WebKit/public/web/modules/serviceworker/WebServiceWorkerContextClient.h
index 18fadb686c9ee2f8df2195005ee0f869eebc87b9..7c612fbb03b4f33a3fdb73105cfecb23a06ed846 100644
--- a/third_party/WebKit/public/web/modules/serviceworker/WebServiceWorkerContextClient.h
+++ b/third_party/WebKit/public/web/modules/serviceworker/WebServiceWorkerContextClient.h
@@ -108,6 +108,10 @@ public:
     // ServiceWorker specific method.
     virtual void didHandleActivateEvent(int eventID, WebServiceWorkerEventResult result) { }
 
+    // Called after ExtendableMessageEvent is handled by the ServiceWorker's
+    // script context.
+    virtual void didHandleExtendableMessageEvent(int eventID, WebServiceWorkerEventResult result) {}

[falken, 2016/01/29 09:47:52]

nit: The other functions are "{ }"

[nhiroki, 2016/02/01 02:05:28]

Done.

+
     // ServiceWorker specific methods. Called after FetchEvent is handled by the
     // ServiceWorker's script context. When no response is provided, the browser
     // should fallback to native fetch.