[RemotePlayback] Implement 'connecting' state

chrome/browser/media/android/remote/remote_media_player_manager.h

Index: chrome/browser/media/android/remote/remote_media_player_manager.h
diff --git a/chrome/browser/media/android/remote/remote_media_player_manager.h b/chrome/browser/media/android/remote/remote_media_player_manager.h
index 0e5173c04f5bdd1961fed54638688f0dadda5a9c..07d8d8b63e23f8cfa897df29d0732147b87086cc 100644
--- a/chrome/browser/media/android/remote/remote_media_player_manager.h
+++ b/chrome/browser/media/android/remote/remote_media_player_manager.h
@@ -34,6 +34,9 @@ class RemoteMediaPlayerManager : public content::BrowserMediaPlayerManager {
   // Callback to trigger when a remote device has been unselected.
   void OnRemoteDeviceUnselected(int player_id);
 
+  // Callback to trigger when the video on a remote device starts playing.
+  void OnRemotePlaybackStarted(int player_id);
+
   // Callback to trigger when the video on a remote device finishes playing.
   void OnRemotePlaybackFinished(int player_id);