Video Player: Support Media Router to cast Drive videos.

ui/file_manager/video_player/js/video_player.js

Index: ui/file_manager/video_player/js/video_player.js
diff --git a/ui/file_manager/video_player/js/video_player.js b/ui/file_manager/video_player/js/video_player.js
index fadab6e61e7d3361ed4601529c794fbc2c8fb327..455cae61a30f01ce08e13f2a7938ce6942c6d0c4 100644
--- a/ui/file_manager/video_player/js/video_player.js
+++ b/ui/file_manager/video_player/js/video_player.js
@@ -277,6 +277,10 @@ VideoPlayer.prototype.prepare = function(videos) {
   else
     videoPlayerElement.removeAttribute('multiple');
 
+  var castButton = queryRequiredElement('.cast-button');
+  castButton.addEventListener('click',
+      this.onCastButtonClicked_.wrap(this));
+
   document.addEventListener('keydown', reloadVideo);
   document.addEventListener('click', reloadVideo);
 };
@@ -359,8 +363,6 @@ VideoPlayer.prototype.loadVideo_ = function(video, opt_callback) {
     if (this.currentCast_) {
       metrics.recordPlayType(metrics.PLAY_TYPE.CAST);
 
-      videoPlayerElement.setAttribute('casting', true);
-
       getRequiredElement('cast-name').textContent =
           this.currentCast_.friendlyName;
 
@@ -372,9 +374,14 @@ VideoPlayer.prototype.loadVideo_ = function(video, opt_callback) {
               return Promise.reject('No casts are available.');
 
             return new Promise(function(fulfill, reject) {
-              chrome.cast.requestSession(
-                  fulfill, reject, undefined, this.currentCast_.label);
+              if (this.currentSession_) {
+                fulfill(this.currentSession_);
+              } else {
+                chrome.cast.requestSession(
+                    fulfill, reject, undefined, this.currentCast_.label);
+              }
             }.bind(this)).then(function(session) {
+              videoPlayerElement.setAttribute('casting', true);
               session.addUpdateListener(this.onCastSessionUpdateBound_);
 
               this.currentSession_ = session;
@@ -503,7 +510,10 @@ VideoPlayer.prototype.unloadVideo = function(opt_keepSession) {
     this.videoElement_ = null;
 
     if (!opt_keepSession && this.currentSession_) {
-      this.currentSession_.stop(callback, callback);
+      if (this.currentSession_.status === chrome.cast.SessionStatus.CONNECTED)

[fukino, 2016/05/18 05:02:21]

bug fix: We should not request stop() if the current session is not connected to
receiver.

[yoshiki, 2016/05/19 07:23:37]

nit: Please add a comment for that.

[fukino, 2016/05/19 08:11:06]

Done.

+        this.currentSession_.stop(callback, callback);
+      else
+        setTimeout(callback);
       this.currentSession_.removeUpdateListener(this.onCastSessionUpdateBound_);
       this.currentSession_ = null;
     } else {
@@ -653,6 +663,49 @@ VideoPlayer.prototype.setCastList = function(casts) {
 };
 
 /**
+ * Tells the availability of cast receivers to VideoPlayeru topdate the
+ * visibility of the cast button..

[yoshiki, 2016/05/19 07:23:37]

nit: JSdoc for the argument.

[fukino, 2016/05/19 08:11:06]

Done.

+ */
+VideoPlayer.prototype.setCastAvailability = function(available) {
+  var videoPlayerElement = getRequiredElement('video-player');
+  if (available) {
+    videoPlayerElement.setAttribute('mr-cast-available', true);
+  } else {
+    videoPlayerElement.removeAttribute('mr-cast-available');
+    if (this.currentCast_)
+      this.onCurrentCastDisappear_();
+  }
+};
+
+/**
+ * Handles click event on cast button to request a session.
+ * @private
+ */
+VideoPlayer.prototype.onCastButtonClicked_ = function() {
+  // This method is called only when Media Router is enabled.
+  // In this case, requestSession() will open a built-in dialog (not a dropdown
+  // menu) to choose the receiver, and callback is called with the session
+  // object after user's operation..
+  chrome.cast.requestSession(
+      function(session) {
+        this.unloadVideo(true);
+        this.loadQueue_.run(function(callback) {
+          this.currentCast_ = {
+            label: session.receiver.label,
+            friendlyName: session.receiver.friendlyName
+          };
+          this.currentSession_ = session;
+          this.reloadCurrentVideo();
+          callback();
+        }.bind(this));
+      }.bind(this),
+      function(error) {
+        if (error.code !== chrome.cast.ErrorCode.CANCEL)
+          console.error('requestSession from cast button failed', error);
+      });
+};
+
+/**
  * Updates the check status of the cast menu items.
  * @private
  */
@@ -696,8 +749,20 @@ VideoPlayer.prototype.onCurrentCastDisappear_ = function() {
  * @private
  */
 VideoPlayer.prototype.onCastSessionUpdate_ = function(alive) {
-  if (!alive)
+  if (!alive) {
+    var videoPlayerElement = getRequiredElement('video-player');
+    videoPlayerElement.removeAttribute('casting');
+
+    // Loads the current video in local player.

[fukino, 2016/05/18 05:02:21]

bug fix: we need to switch to local player even when the cast session is
terminated without any user operation in video player. (e.g. terminated by other
apps which tries to use the receiver).

     this.unloadVideo();
+    this.loadQueue_.run(function(callback) {
+      this.currentCast_ = null;
+      if (!chrome.cast.usingPresentationApi)
+        this.updateCheckOnCastMenu_();
+      this.reloadCurrentVideo();
+      callback();
+    }.wrap(this));
+  }
 };
 
 /**