Make navigator.serviceWorker.ready resolve with the controller.

Source/modules/serviceworkers/ServiceWorkerContainer.h

Index: Source/modules/serviceworkers/ServiceWorkerContainer.h
diff --git a/Source/modules/serviceworkers/ServiceWorkerContainer.h b/Source/modules/serviceworkers/ServiceWorkerContainer.h
index 08110785005110dd5470bc0098a9a218271fbffc..253aa4a4fd97cc590ca26e8581aa1d92c4062cfd 100644
--- a/Source/modules/serviceworkers/ServiceWorkerContainer.h
+++ b/Source/modules/serviceworkers/ServiceWorkerContainer.h
@@ -64,11 +64,12 @@ public:
 
     void detachClient();
 
+    PassRefPtrWillBeRawPtr<ServiceWorker> controller() { return m_controller.get(); }
+    ScriptPromise ready(ScriptState*);
+
     ScriptPromise registerServiceWorker(ScriptState*, const String& pattern, const Dictionary&);
     ScriptPromise unregisterServiceWorker(ScriptState*, const String& scope = String());
 
-    PassRefPtrWillBeRawPtr<ServiceWorker> controller() { return m_controller.get(); }
-
     // WebServiceWorkerProviderClient overrides.
     virtual void setController(blink::WebServiceWorker*) OVERRIDE;
     virtual void dispatchMessageEvent(const blink::WebString& message, const blink::WebMessagePortChannelArray&) OVERRIDE;