[Media Router] Use DialMediaSinkService in MediaRouterMojoImpl

chrome/browser/media/router/media_router.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_MEDIA_ROUTER_MEDIA_ROUTER_H_
 #define CHROME_BROWSER_MEDIA_ROUTER_MEDIA_ROUTER_H_
 
 #include <stdint.h>
 
 #include <string>
@@ skipping 160 matching lines @@
       const MediaSource::Id& source_id,
       const std::string& search_input,
       const std::string& domain,
       const MediaSinkSearchResponseCallback& sink_callback) = 0;
 
   // Notifies the Media Router that the list of MediaSinks discovered by a
   // MediaSinkService has been updated.
   // |provider_name|: Name of the MediaSinkService providing the sinks.
   // |sinks|: sinks discovered by MediaSinkService.
   virtual void ProvideSinks(const std::string& provider_name,
-                            const std::vector<MediaSinkInternal>& sinks) = 0;
+                            std::vector<MediaSinkInternal> sinks) = 0;

[imcheng, 2017/05/26 01:26:00]

similar to the other comment about using std::move. This method is used in
base::Bind as a base::Callback. So |sinks| is the reference is to the vector
that was (safely) copied into the callback's internal storage.

[zhaobin, 2017/05/26 20:59:40]

To avoid copy as Mark suggested...

 
   // Adds |callback| to listen for state changes for presentation connected to
   // |route_id|. The returned Subscription object is owned by the caller.
   // |callback| will be invoked whenever there are state changes, until the
   // caller destroys the Subscription object.
   virtual std::unique_ptr<PresentationConnectionStateSubscription>
   AddPresentationConnectionStateChangedCallback(
       const MediaRoute::Id& route_id,
       const content::PresentationConnectionStateChangedCallback& callback) = 0;
 
@@ skipping 73 matching lines @@
   // Removes the MediaRouteController for |route_id| from the list of
   // controllers held by |this|. Called by MediaRouteController when it is
   // invalidated.
   virtual void DetachRouteController(const MediaRoute::Id& route_id,
                                      MediaRouteController* controller) = 0;
 };
 
 }  // namespace media_router
 
 #endif  // CHROME_BROWSER_MEDIA_ROUTER_MEDIA_ROUTER_H_