MD History: hide tooltip promo when drawer is swiped open

ui/webui/resources/cr_elements/cr_toolbar/cr_toolbar.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.
 
 Polymer({
   is: 'cr-toolbar',
 
   properties: {
     // Name to display in the toolbar, in titlecase.
     pageName: String,
@@ skipping 17 matching lines @@
 
     // Controls whether the menu button is shown at the start of the menu.
     showMenu: {
       type: Boolean,
       value: false
     },
 
     // Whether to show menu promo tooltip.
     showMenuPromo: {
       type: Boolean,
-      value: false,
+      notify: true,

[calamity, 2016/10/27 02:12:41]

Is it necessary to remove the value: false here? Can history-app set the
loadTimeData value in its ready() instead?

It's weird to require clients to set a value on showMenuPromo for the title to
render.

     },
 
     closeMenuPromo: String,
 
     /** @private */
     narrow_: {
       type: Boolean,
       reflectToAttribute: true
     },
 
@@ skipping 14 matching lines @@
   },
 
   /** @private */
   onClosePromoTap_: function() {
     this.showMenuPromo = false;
   },
 
   /** @private */
   onMenuTap_: function() {
     this.fire('cr-menu-tap');
-    this.onClosePromoTap_();
   },
 
   /** @private */
   possiblyShowMenuPromo_: function() {
     Polymer.RenderStatus.afterNextRender(this, function() {
       if (this.showMenu && this.showMenuPromo && !this.showingSearch_) {
         this.$$('#menuPromo').animate({
           opacity: [0, .9],
         }, /** @type {!KeyframeEffectOptions} */({
           duration: 500,
           fill: 'forwards'
         }));
         this.fire('cr-menu-promo-shown');
       }
     }.bind(this));
   },
 
   /**
    * @param {string} title
    * @param {boolean} showMenuPromo
    * @return {string} The title if the menu promo isn't showing, else "".
    */
   titleIfNotShowMenuPromo_: function(title, showMenuPromo) {
     return showMenuPromo ? '' : title;
   },
 });