Handle BrowserBack to close the window in built-in media players.

Android apps are closed by BrowserBack key on Chrome OS.
To make the built-in app's behavior consistent and keep the app alive, we close
the built-in media players on BrowserBack.

Bug: 807521
Test: Manually tested.
Cq-Include-Trybots: master.tryserver.chromium.linux:closure_compilation
Change-Id: Ic5097216bc83f6fd78db6f7d9155b0705b2eea3b
Reviewed-on: https://chromium-review.googlesource.com/940784Reviewed-by: Tatsuhisa Yamaguchi <yamaguchi@chromium.org>
Commit-Queue: Naoki Fukino <fukino@chromium.org>
Cr-Commit-Position: refs/heads/master@{#539836}

ui/file_manager/audio_player/elements/audio_player.js

@@ -18,89 +18,55 @@ Polymer({
      * Flag whether the audio is playing or paused. True if playing, or false
      * paused.
      */
-    playing: {
-      type: Boolean,
-      observer: 'playingChanged',
-      reflectToAttribute: true
-    },
+    playing:
+        {type: Boolean, observer: 'playingChanged', reflectToAttribute: true},
 
     /**
      * Current elapsed time in the current music in millisecond.
      */
-    time: {
-      type: Number,
-      observer: 'timeChanged'
-    },
+    time: {type: Number, observer: 'timeChanged'},
 
     /**
      * Whether the shuffle button is ON.
      */
-    shuffle: {
-      type: Boolean,
-      notify: true
-    },
+    shuffle: {type: Boolean, notify: true},
 
     /**
      * What mode the repeat button idicates.
      * repeat-modes can be "no-repeat", "repeat-all", "repeat-one".
      */
-    repeatMode: {
-      type: String,
-      notify: true
-    },
+    repeatMode: {type: String, notify: true},
 
     /**
      * The audio volume. 0 is silent, and 100 is maximum loud.
      */
-    volume: {
-      type: Number,
-      notify: true
-    },
+    volume: {type: Number, notify: true},
 
     /**
      * Whether the playlist is expanded or not.
      */
-    playlistExpanded: {
-      type: Boolean,
-      notify: true
-    },
+    playlistExpanded: {type: Boolean, notify: true},
     /**
      * Whether the artwork is expanded or not.
      */
-    trackInfoExpanded: {
-      type: Boolean,
-      notify: true
-    },
+    trackInfoExpanded: {type: Boolean, notify: true},
 
     /**
      * Track index of the current track.
      */
-    currentTrackIndex: {
-      type: Number,
-      observer: 'currentTrackIndexChanged'
-    },
+    currentTrackIndex: {type: Number, observer: 'currentTrackIndexChanged'},
 
     /**
      * URL of the current track. (exposed publicly for tests)
      */
-    currenttrackurl: {
-      type: String,
-      value: '',
-      reflectToAttribute: true
-    },
+    currenttrackurl: {type: String, value: '', reflectToAttribute: true},
 
     /**
      * The number of played tracks. (exposed publicly for tests)
      */
-    playcount: {
-      type: Number,
-      value: 0,
-      reflectToAttribute: true
-    },
-
-    ariaLabels: {
-      type: Object
-    }
+    playcount: {type: Number, value: 0, reflectToAttribute: true},
+
+    ariaLabels: {type: Object}
   },
 
   /**
@@ -135,6 +101,13 @@ Polymer({
     this.$.audio.addEventListener('loadedmetadata', onAudioStatusUpdatedBound);
   },
 
+  /**
+   * Starts playing in inner audio element.
+   */
+  play: function() {
+    this.$.audio.play();
+  },
+
   /**
    * Invoked when trackList.currentTrackIndex is changed.
    * @param {number} newValue new value.

ui/file_manager/audio_player/js/audio_player.js

@@ -285,7 +285,7 @@ AudioPlayer.prototype.select_ = function(newTrack) {
   // Run asynchronously after an event of current track change is delivered.
   setTimeout(function() {
     if (!window.appReopen)
-      this.player_.$.audio.play();
+      this.player_.play();
 
     window.appState.position = this.currentTrackIndex_;
     window.appState.time = 0;
@@ -365,6 +365,7 @@ AudioPlayer.prototype.onResize_ = function(event) {
 AudioPlayer.prototype.onKeyDown_ = function(event) {
   switch (util.getKeyModifiers(event) + event.key) {
     case 'Ctrl-w': // Ctrl+W => Close the player.
+    case 'BrowserBack':
       chrome.app.window.current().close();
       break;
 
@@ -511,7 +512,7 @@ AudioPlayer.prototype.onTrackInfoExpandedChanged_ = function(newValue) {
 
   if (this.isTrackInfoExpanded_ !== newValue) {
     this.isTrackInfoExpanded_ = newValue;
-    var state = chrome.app.window.current()
+    var state = chrome.app.window.current();
     var newHeight = window.outerHeight;
     if (newValue) {
       state.innerBounds.minHeight = AudioPlayer.EXPANDED_MODE_MIN_HEIGHT;

ui/file_manager/gallery/js/gallery.js

@@ -779,6 +779,7 @@ Gallery.prototype.onKeyDown_ = function(event) {
       break;
 
     case 'Escape':
+    case 'BrowserBack':
       window.close();
       break;
   }

ui/file_manager/video_player/js/video_player.js

@@ -74,6 +74,9 @@ function FullWindowVideoControls(
       case 'j':
         this.bigSkip(false);
         break;
+      case 'BrowserBack':
+        chrome.app.window.current().close();
+        break;
       case 'MediaStop':
         // TODO: Define "Stop" behavior.
         break;