Files.app: Let the PreviewPanel class control the visibility of the preview panel.

chrome/browser/resources/file_manager/js/main_scripts.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.
 
 // The include directives are put into Javascript-style comments to prevent
 // parsing errors in non-flattened mode. The flattener still sees them.
 // Note that this makes the flattener to comment out the first line of the
 // included file but that's all right since any javascript file should start
 // with a copyright comment anyway.
 
@@ skipping 83 matching lines @@
 //<include src="file_type.js"/>
 //<include src="file_watcher.js"/>
 //<include src="folder_shortcuts_data_model.js"/>
 //<include src="navigation_list.js"/>
 //<include src="scrollbar.js"/>
 //<include src="share_client.js"/>
 //<include src="share_dialog.js"/>
 //<include src="suggest_apps_dialog.js"/>
 //<include src="text_measure.js"/>
 //<include src="tree.css.js"/>
+//<include src="ui/preview_panel.js"/>
 //<include src="url_constants.js"/>
 //<include src="volume_manager.js"/>
 //<include src="media/media_util.js"/>
 //<include src="metadata/metadata_cache.js"/>
 //<include src="default_action_dialog.js"/>
 //<include src="file_manager_commands.js"/>
 
 // // For accurate load performance tracking place main.js should be
 // // the last include to include.
 //<include src="main.js"/>
 
 // Global fileManager reference useful for poking at from the console.
 window.fileManager = fileManager;
 
 // Exports
 window.util = util;
 window.FileOperationManagerWrapper = FileOperationManagerWrapper;
 
 window.unload = unload;
 
 })();