MD Bookmarks: Enable the delete button in the toolbar overlay

chrome/test/data/webui/md_bookmarks/test_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.
+
+/**
+ * Creates and returns a CommandManager which tracks what commands are executed.
+ * @constructor
+ * @extends {bookmarks.CommandManager}
+ */
+function TestCommandManager() {
+  var commandManager = document.createElement('bookmarks-command-manager');
+  var lastCommand = null;
+  var lastCommandIds = null;
+
+  var realHandle = commandManager.handle.bind(commandManager);
+  commandManager.handle = function(command, itemIds) {
+    lastCommand = command;
+    lastCommandIds = itemIds;
+    realHandle(command, itemIds);
+  };
+
+  commandManager.assertLastCommand = function (command, ids) {
+    assertEquals(command, lastCommand);
+    if (ids)
+      assertDeepEquals(ids, normalizeSet(lastCommandIds));
+    lastCommand = null;
+    lastCommandIds = null;
+  };
+
+  return commandManager;
+}