Enabled Mosaic view on each volume.

chrome/browser/resources/file_manager/js/file_tasks.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.
 
 /**
  * This object encapsulates everything related to tasks execution.
  *
  * @param {FileManager} fileManager FileManager instance.
  * @param {Object=} opt_params File manager load parameters.
  * @constructor
@@ skipping 440 matching lines @@
 
     var context = {
       // We show the root label in readonly warning (e.g. archive name).
       readonlyDirName: readonlyDirName,
       curDirEntry: currentDir,
       saveDirEntry: readonly ? downloadsDir : null,
       searchResults: fm.directoryModel_.isSearching(),
       metadataCache: fm.metadataCache_,
       pageState: this.params_,
       onClose: onClose,
-      allowMosaic: fm.isOnDrive(),
       onThumbnailError: function(imageURL) {
         fm.metadataCache_.refreshFileMetadata(imageURL);
       },
       displayStringFunction: strf
     };
     galleryFrame.contentWindow.Gallery.open(context, allUrls, urls);
   }.bind(this);
 
   galleryFrame.src = 'gallery.html';
   fm.openFilePopup_(galleryFrame, fm.updateTitle_.bind(fm));
@@ skipping 130 matching lines @@
       title,
       message,
       items, defaultIdx,
       onSuccess);
 };
 
 FileTasks.decorate('display');
 FileTasks.decorate('updateMenuItem');
 FileTasks.decorate('execute');
 FileTasks.decorate('executeDefault');