MD Bookmarks: Add 'Open' command, to open in either the BMM or in new tabs

chrome/test/data/webui/md_bookmarks/test_util.js

 // Copyright 2016 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.
 
 /**
  * Replace the current body of the test with a new element.
  * @param {Element} element
  */
 function replaceBody(element) {
   PolymerTest.clearBody();
@@ skipping 76 matching lines @@
  * @template T
  */
 function normalizeSet(set) {
   return Array.from(set).sort();
 }
 
 /**
  * Sends a custom click event to |element|.
  * @param {HTMLElement} element
  * @param {Object=} config
+ * @param {string=} eventname
  */
-function customClick(element, config) {
+function customClick(element, config, eventname) {
   var props = {
     bubbles: true,
     cancelable: true,
+    button: 0,
     buttons: 1,
     shiftKey: false,
     ctrlKey: false,
+    detail: 1,
   };
 
   if (config) {
     for (var key in config)
       props[key] = config[key];
   }
 
+  eventname = eventname || 'click';
+
   element.dispatchEvent(new MouseEvent('mousedown', props));
   element.dispatchEvent(new MouseEvent('mouseup', props));
-  element.dispatchEvent(new MouseEvent('click', props));
+  element.dispatchEvent(new MouseEvent(eventname, props));
 }
 
 /**
  * Returns a folder node beneath |rootNode| which matches |id|.
  * @param {BookmarksFolderNodeElement} rootNode
  * @param {string} id
  * @return {BookmarksFolderNodeElement}
  */
 function findFolderNode(rootNode, id) {
   var nodes = [rootNode];
   var node;
   while (nodes.length) {
     node = nodes.pop();
     if (node.itemId == id)
       return node;
 
     node.root.querySelectorAll('bookmarks-folder-node')
         .forEach((x) => {nodes.unshift(x)});
   }
 }