Gallery: Register unload handler to 'pagehide' event.

ui/file_manager/gallery/js/gallery.js

 // Copyright 2014 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.
 
 /**
- * Called from the main frame when unloading.
- * @param {boolean=} opt_exiting True if the app is exiting.
- */
-function unload(opt_exiting) { gallery.onUnload(opt_exiting); }
-
-/**
  * Overrided metadata worker's path.
  * @type {string}
  */
 ContentProvider.WORKER_SCRIPT = '/js/metadata_worker.js';
 
 /**
  * Data model for gallery.
  *
  * @param {!MetadataCache} metadataCache Metadata cache.
  * @constructor
@@ skipping 339 matching lines @@
   // the observer is not going to work.
   if (!this.context_.searchResults && this.context_.curDirEntry) {
     this.metadataCacheObserverId_ = this.metadataCache_.addObserver(
         this.context_.curDirEntry,
         MetadataCache.CHILDREN,
         'thumbnail',
         this.updateThumbnails_.bind(this));
   }
   this.volumeManager_.addEventListener(
       'externally-unmounted', this.onExternallyUnmountedBound_);
+  // The 'pagehide' event is called when the app window is closed.
+  window.addEventListener('pagehide', this.onPageHide_.bind(this));
 }
 
 /**
  * Gallery extends cr.EventTarget.
  */
 Gallery.prototype.__proto__ = cr.EventTarget.prototype;
 
 /**
  * Tools fade-out timeout in milliseconds.
  * @const
@@ skipping 33 matching lines @@
     return;
 
   if (this.volumeManager_.getVolumeInfo(this.selectedEntry_) ===
       event.volumeInfo) {
     window.close();
   }
 };
 
 /**
  * Unloads the Gallery.
- * @param {boolean=} opt_exiting True if the app is exiting.
+ * @private
  */
-Gallery.prototype.onUnload = function(opt_exiting) {
+Gallery.prototype.onPageHide_ = function() {
   if (this.metadataCacheObserverId_ !== null)
     this.metadataCache_.removeObserver(this.metadataCacheObserverId_);
   this.volumeManager_.removeEventListener(
       'externally-unmounted', this.onExternallyUnmountedBound_);
 };
 
 /**
  * Initializes a toolbar button.
  *
  * @param {string} className Class to add.
@@ skipping 621 matching lines @@
 };
 
 /**
  * Loads entries.
  * @param {!Array.<Entry>} entries Array of entries.
  * @param {!Array.<Entry>} selectedEntries Array of selected entries.
  */
 window.loadEntries = function(entries, selectedEntries) {
   gallery.load(entries, selectedEntries);
 };