MD WebUI: Do not restore focus from <cr-shared-menu> when closing with tap

ui/webui/resources/cr_elements/cr_shared_menu/cr_shared_menu.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.
 
 /** Same as paper-menu-button's custom easing cubic-bezier param. */
 var SLIDE_CUBIC_BEZIER = 'cubic-bezier(0.3, 0.95, 0.5, 1)';
 
 Polymer({
   is: 'cr-shared-menu',
 
@@ skipping 74 matching lines @@
           }
         }];
       }
     }
   },
 
   keyBindings: {
     'tab': 'onTabPressed_',
   },
 
+  listeners: {
+    'dropdown.iron-overlay-canceled': 'onOverlayCanceled_',
+  },
+
   /**
    * The last anchor that was used to open a menu. It's necessary for toggling.
    * @private {?Element}
    */
   lastAnchor_: null,
 
   /**
    * The first focusable child in the menu's light DOM.
    * @private {?Element}
    */
@@ skipping 22 matching lines @@
   },
 
   /**
    * Opens the menu at the anchor location.
    * @param {!Element} anchor The location to display the menu.
    * @param {!Object} itemData The contextual item's data.
    */
   openMenu: function(anchor, itemData) {
     this.itemData = itemData;
     this.lastAnchor_ = anchor;
+    this.$.dropdown.restoreFocusOnClose = true;
 
     var focusableChildren = Polymer.dom(this).querySelectorAll(
         '[tabindex]:not([hidden]),button:not([hidden])');
     if (focusableChildren.length > 0) {
       this.$.dropdown.focusTarget = focusableChildren[0];
       this.firstFocus_ = focusableChildren[0];
       this.lastFocus_ = focusableChildren[focusableChildren.length - 1];
     }
 
     // Move the menu to the anchor.
@@ skipping 40 matching lines @@
 
   /**
    * Ensure the menu is reset properly when it is closed by the dropdown (eg,
    * clicking outside).
    * @private
    */
   menuOpenChanged_: function() {
     if (!this.menuOpen)
       this.itemData = null;
   },
+
+  /**
+   * Prevent focus restoring when tapping outside the menu. This stops the
+   * focus moving around unexpectedly when closing the menu with the mouse.
+   * @param {CustomEvent} e
+   * @private
+   */
+  onOverlayCanceled_: function(e) {
+    if (e.detail.type == 'tap')
+      this.$.dropdown.restoreFocusOnClose = false;
+  },
 });