ServiceWorker: Add support for .skipWaiting and controllerchange event(1/3)

public/web/WebServiceWorkerContextClient.h

Index: public/web/WebServiceWorkerContextClient.h
diff --git a/public/web/WebServiceWorkerContextClient.h b/public/web/WebServiceWorkerContextClient.h
index cfb7add05c7a726565b858d6852768bb1fd0a016..493205e0674520b7a9ef977f4a8f73b3167dc5b3 100644
--- a/public/web/WebServiceWorkerContextClient.h
+++ b/public/web/WebServiceWorkerContextClient.h
@@ -32,6 +32,7 @@
 #define WebServiceWorkerContextClient_h
 
 #include "WebWorkerPermissionClientProxy.h"
+#include "public/platform/WebCallback.h"
 #include "public/platform/WebMessagePortChannel.h"
 #include "public/platform/WebServiceWorkerClientsInfo.h"
 #include "public/platform/WebServiceWorkerEventResult.h"
@@ -144,6 +145,10 @@ public:
     // Callee receives ownership of the passed vector.
     // FIXME: Blob refs should be passed to maintain ref counts. crbug.com/351753
     virtual void postMessageToClient(int clientID, const WebString&, WebMessagePortChannelArray*) { BLINK_ASSERT_NOT_REACHED(); }
+
+    // Ownership of the passed callback is transferred to the callee, callee
+    // should delete the callback after run.
+    virtual void skipWaiting(WebCallback*) { BLINK_ASSERT_NOT_REACHED(); }
 };
 
 } // namespace blink