Gallery: Remove the back button that is used to let users go back to Files.app.

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.
 
 'use strict';
 
 /**
  * Called from the main frame when unloading.
  * @param {boolean=} opt_exiting True if the app is exiting.
  */
@@ skipping 10 matching lines @@
  * Gallery for viewing and editing image files.
  *
  * @param {!VolumeManager} volumeManager The VolumeManager instance of the
  *     system.
  * @class
  * @constructor
  */
 function Gallery(volumeManager) {
   this.context_ = {
     appWindow: chrome.app.window.current(),
-    onBack: function() {},
     onClose: function() { close(); },
     onMaximize: function() {
       var appWindow = chrome.app.window.current();
       if (appWindow.isMaximized())
         appWindow.restore();
       else
         appWindow.maximize();
     },
     onMinimize: function() { chrome.app.window.current().minimize(); },
     onAppRegionChanged: function() {},
@@ skipping 81 matching lines @@
  * Closes gallery when a volume containing the selected item is unmounted.
  * @param {!Event} event The unmount event.
  * @private
  */
 Gallery.prototype.onExternallyUnmounted_ = function(event) {
   if (!this.selectedEntry_)
     return;
 
   if (this.volumeManager_.getVolumeInfo(this.selectedEntry_) ===
       event.volumeInfo) {
-    this.onBack_();
+    close();
   }
 };
 
 /**
  * Unloads the Gallery.
  * @param {boolean} exiting True if the app is exiting.
  */
 Gallery.prototype.onUnload = function(exiting) {
   if (this.metadataCacheObserverId_ !== null)
     this.metadataCache_.removeObserver(this.metadataCacheObserverId_);
@@ skipping 10 matching lines @@
   // Initialize the dialog label.
   cr.ui.dialogs.BaseDialog.OK_LABEL = str('GALLERY_OK_LABEL');
   cr.ui.dialogs.BaseDialog.CANCEL_LABEL = str('GALLERY_CANCEL_LABEL');
 
   var content = util.createChild(this.container_, 'content');
   content.addEventListener('click', this.onContentClick_.bind(this));
 
   this.header_ = util.createChild(this.container_, 'header tool dimmable');
   this.toolbar_ = util.createChild(this.container_, 'toolbar tool dimmable');
 
-  var backButton = util.createChild(this.container_,
-                                    'back-button tool dimmable');
-  util.createChild(backButton);
-  backButton.addEventListener('click', this.onBack_.bind(this));
-
   var preventDefault = function(event) { event.preventDefault(); };
 
   var minimizeButton = util.createChild(this.header_,
                                         'minimize-button tool dimmable',
                                         'button');
   minimizeButton.tabIndex = -1;
   minimizeButton.addEventListener('click', this.onMinimize_.bind(this));
   minimizeButton.addEventListener('mousedown', preventDefault);
 
   var maximizeButton = util.createChild(this.header_,
@@ skipping 150 matching lines @@
     /* TODO: consider nice blow-up animation for the first image */
     this.slideMode_.enter(null, function() {
         // Flash the toolbar briefly to show it is there.
         this.inactivityWatcher_.kick(Gallery.FIRST_FADE_TIMEOUT);
       }.bind(this),
       maybeLoadMosaic);
   }
 };
 
 /**
- * Closes the Gallery and go to Files.app.
- * @private
- */
-Gallery.prototype.back_ = function() {
-  if (util.isFullScreen(this.context_.appWindow)) {
-    util.toggleFullScreen(this.context_.appWindow,
-                          false);  // Leave the full screen mode.
-  }
-  this.context_.onBack(this.getSelectedEntries());
-};
-
-/**
- * Handles user's 'Back' action (Escape or a click on the X icon).
- * @private
- */
-Gallery.prototype.onBack_ = function() {
-  this.executeWhenReady(this.back_.bind(this));
-};
-
-/**
  * Handles user's 'Close' action.
  * @private
  */
 Gallery.prototype.onClose_ = function() {
   this.executeWhenReady(this.context_.onClose);
 };
 
 /**
  * Handles user's 'Maximize' action (Escape or a click on the X icon).
  * @private
@@ skipping 236 matching lines @@
 
   if (this.currentMode_.onKeyDown(event))
     return;
 
   switch (util.getKeyModifiers(event) + event.keyIdentifier) {
     case 'U+0008': // Backspace.
       // The default handler would call history.back and close the Gallery.
       event.preventDefault();
       break;
 
-    case 'U+001B':  // Escape
-      // Swallow Esc if it closed the Share menu, otherwise close the Gallery.
-      if (!wasSharing)
-        this.onBack_();
-      break;
-
     case 'U+004D':  // 'm' switches between Slide and Mosaic mode.
       this.toggleMode_(null, event);
       break;
 
     case 'U+0056':  // 'v'
       this.slideMode_.startSlideshow(SlideMode.SLIDESHOW_INTERVAL_FIRST, event);
       break;
 
     case 'U+007F':  // Delete
     case 'Shift-U+0033':  // Shift+'3' (Delete key might be missing).
@@ skipping 262 matching lines @@
   ]).then(function(args) {
     var backgroundComponents = args[0];
     var entries = args[1];
     window.loadTimeData.data = backgroundComponents.stringData;
     var gallery = new Gallery(backgroundComponents.volumeManager);
     gallery.load(entries.allEntries, entries.selectedEntries);
   }).catch(function(error) {
     console.error(error.stack || error);
   });
 });