Video Player: Support Media Router to cast Drive videos.

ui/file_manager/video_player/js/media_controls.js

 // Copyright (c) 2012 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.
 
 /**
  * @fileoverview MediaControls class implements media playback controls
  * that exist outside of the audio/video HTML element.
  */
 
 /**
@@ skipping 843 matching lines @@
 function VideoControls(
     containerElement, onMediaError, opt_fullScreenToggle, opt_stateIconParent) {
   MediaControls.call(this, containerElement, onMediaError);
 
   this.container_.classList.add('video-controls');
   this.initPlayButton();
   this.initTimeControls();
   this.initVolumeControls();
   this.initSubtitlesButton();
 
-  // Create the cast button.
+  // Create the cast menu button.
   // We need to use <button> since cr.ui.MenuButton.decorate modifies prototype
   // chain, by which <files-icon-button> will not work correctly.
   // TODO(fukino): Find a way to use files-icon-button consistently.
   this.castButton_ = this.createControl(
       'cast media-button', undefined, 'button');
   this.castButton_.setAttribute('menu', '#cast-menu');
   this.castButton_.setAttribute('aria-label', str('VIDEO_PLAYER_PLAY_ON'));
   this.castButton_.setAttribute('state', MediaControls.ButtonStateType.DEFAULT);
   this.castButton_.appendChild(document.createElement('files-ripple'));
   cr.ui.decorate(this.castButton_, cr.ui.MenuButton);
 
+  // Create the cast button, which is a normal button and is used when we cast
+  // videos usign Media Router.
+  this.createButton('cast-button');
+
   if (opt_fullScreenToggle) {
     this.fullscreenButton_ =
         this.createButton('fullscreen', opt_fullScreenToggle);
     this.fullscreenButton_.setAttribute('aria-label',
         str('VIDEO_PLAYER_FULL_SCREEN_BUTTON_LABEL'));
   }
 
   if (opt_stateIconParent) {
     this.stateIcon_ = this.createControl(
         'playback-state-icon', opt_stateIconParent);
@@ skipping 194 matching lines @@
   } else {
     this.container_.removeAttribute('fullscreen');
   }
 
   if (this.fullscreenButton_) {
     this.fullscreenButton_.setAttribute('aria-label',
         fullscreen ? str('VIDEO_PLAYER_EXIT_FULL_SCREEN_BUTTON_LABEL')
                    : str('VIDEO_PLAYER_FULL_SCREEN_BUTTON_LABEL'));;
   }
 };