[MD Bookmarks] Add undo/redo functionality to MD Bookmarks.

chrome/browser/resources/md_bookmarks/command_manager.js

 // Copyright 2017 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.
 
 /**
  * @fileoverview Element which shows context menus and handles keyboard
  * shortcuts.
  */
 cr.define('bookmarks', function() {
 
@@ skipping 40 matching lines @@
       /** @private {Object<Command, string>} */
       this.shortcuts_ = {};
       this.shortcuts_[Command.EDIT] = cr.isMac ? 'enter' : 'f2';
       this.shortcuts_[Command.COPY] = cr.isMac ? 'meta+c' : 'ctrl+c';
       this.shortcuts_[Command.DELETE] =
           cr.isMac ? 'delete backspace' : 'delete';
       this.shortcuts_[Command.OPEN_NEW_TAB] =
           cr.isMac ? 'meta+enter' : 'ctrl+enter';
       this.shortcuts_[Command.OPEN_NEW_WINDOW] = 'shift+enter';
       this.shortcuts_[Command.OPEN] = cr.isMac ? 'meta+down' : 'enter';
+      this.shortcuts_[Command.UNDO] =
+          cr.isMac ? 'meta+z' : 'ctrl+z ctrl+shift+z';

[tsergeant, 2017/05/23 07:34:02]

Is ctrl-shift-z meant to be REDO? That's what happens elsewhere in Chrome.

[calamity, 2017/05/24 07:44:14]

Oops, fixed.

+      this.shortcuts_[Command.REDO] = cr.isMac ? 'meta+shift+z' : 'ctrl+y';
     },
 
     detached: function() {
       CommandManager.instance_ = null;
       document.removeEventListener('open-item-menu', this.boundOnOpenItemMenu_);
       document.removeEventListener('keydown', this.boundOnKeydown_);
     },
 
     /**
      * Display the command context menu at (|x|, |y|) in window co-ordinates.
@@ skipping 29 matching lines @@
      * Commands which appear in the context menu should be implemented
      * separately using `isCommandVisible_` and `isCommandEnabled_`.
      * @param {Command} command
      * @param {!Set<string>} itemIds
      * @return {boolean}
      */
     canExecute: function(command, itemIds) {
       switch (command) {
         case Command.OPEN:
           return itemIds.size > 0;
+        case Command.UNDO:
+        case Command.REDO:
+          return true;
         default:
           return this.isCommandVisible_(command, itemIds) &&
               this.isCommandEnabled_(command, itemIds);
       }
     },
 
     /**
      * @param {Command} command
      * @param {!Set<string>} itemIds
      * @return {boolean} True if the command should be visible in the context
@@ skipping 51 matching lines @@
           chrome.bookmarkManagerPrivate.copy(idList, function() {
             // TODO(jiaxi): Add toast later.
           });
           break;
         case Command.DELETE:
           chrome.bookmarkManagerPrivate.removeTrees(
               Array.from(this.minimizeDeletionSet_(itemIds)), function() {
                 // TODO(jiaxi): Add toast later.
               });
           break;
+        case Command.UNDO:
+          chrome.bookmarkManagerPrivate.undo();
+          break;
+        case Command.REDO:
+          chrome.bookmarkManagerPrivate.redo();
+          break;
         case Command.OPEN_NEW_TAB:
         case Command.OPEN_NEW_WINDOW:
         case Command.OPEN_INCOGNITO:
           this.openUrls_(this.expandUrls_(itemIds), command);
           break;
         case Command.OPEN:
           var isFolder = itemIds.size == 1 &&
               this.containsMatchingNode_(itemIds, function(node) {
                 return !node.url;
               });
@@ skipping 218 matching lines @@
 
   /** @return {!bookmarks.CommandManager} */
   CommandManager.getInstance = function() {
     return assert(CommandManager.instance_);
   };
 
   return {
     CommandManager: CommandManager,
   };
 });