Add GetCurrentRoutes() to MediaRouter API, ensure dialog has routes at init

chrome/browser/ui/webui/media_router/media_router_ui.h

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CHROME_BROWSER_UI_WEBUI_MEDIA_ROUTER_MEDIA_ROUTER_UI_H_
 #define CHROME_BROWSER_UI_WEBUI_MEDIA_ROUTER_MEDIA_ROUTER_UI_H_
 
 #include <memory>
 #include <set>
 #include <string>
@@ skipping 129 matching lines @@
   const std::set<MediaCastMode>& cast_modes() const { return cast_modes_; }
   const std::unordered_map<MediaRoute::Id, MediaCastMode>& current_cast_modes()
       const {
     return current_cast_modes_;
   }
   const content::WebContents* initiator() const { return initiator_; }
 
   // Marked virtual for tests.
   virtual const std::string& GetRouteProviderExtensionId() const;
 
+  const std::vector<MediaRoute>& GetRoutes();
+
   // Called to track UI metrics.
   void SetUIInitializationTimer(const base::Time& start_time);
   void OnUIInitiallyLoaded();
   void OnUIInitialDataReceived();
 
   void UpdateMaxDialogHeight(int height);
 
   void InitForTest(MediaRouter* router,
                    content::WebContents* initiator,
                    MediaRouterWebUIMessageHandler* handler,
@@ skipping 119 matching lines @@
   MediaRouterWebUIMessageHandler* handler_;
 
   // These are non-null while this instance is registered to receive
   // updates from them.
   std::unique_ptr<IssuesObserver> issues_observer_;
   std::unique_ptr<MediaRoutesObserver> routes_observer_;
 
   // Set to true by |handler_| when the UI has been initialized.
   bool ui_initialized_;
 
+  bool initial_routes_received_;
+
   // Set to -1 if not tracking a pending route request.
   int current_route_request_id_;
 
   // Sequential counter for route requests. Used to update
   // |current_route_request_id_| when there is a new route request.
   int route_request_counter_;
 
   // Used for locale-aware sorting of sinks by name. Set during |InitCommon()|
   // using the current locale. Set to null
   std::unique_ptr<icu::Collator> collator_;
@@ skipping 35 matching lines @@
   // NOTE: Weak pointers must be invalidated before all other member variables.
   // Therefore |weak_factory_| must be placed at the end.
   base::WeakPtrFactory<MediaRouterUI> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(MediaRouterUI);
 };
 
 }  // namespace media_router
 
 #endif  // CHROME_BROWSER_UI_WEBUI_MEDIA_ROUTER_MEDIA_ROUTER_UI_H_