[MD History] Make sidebar menu respond to spacebar.

chrome/browser/resources/md_history/app.crisper.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.
 function PromiseResolver() {
   this.resolve_;
   this.reject_;
   this.promise_ = new Promise(function(resolve, reject) {
     this.resolve_ = resolve;
     this.reject_ = reject;
   }.bind(this));
@@ skipping 8536 matching lines @@
       type: String,
       notify: true
     },
     route: Object,
     showFooter: Boolean,
     drawer: {
       type: Boolean,
       reflectToAttribute: true
     }
   },
+  listeners: {
+    keydown: 'onKeydown_'
+  },
+  onKeydown_: function(e) {
+    if (e.code == 'Space') e.path[0].click();
+  },
   onSelectorActivate_: function() {
     this.fire('history-close-drawer');
   },
   onClearBrowsingDataTap_: function(e) {
     var browserService = md_history.BrowserService.getInstance();
     browserService.recordAction('InitClearBrowsingData');
     browserService.openClearBrowsingData();
     e.preventDefault();
   },
   getQueryString_: function(route) {
@@ skipping 191 matching lines @@
 
        case HistoryRange.MONTH:
         histogramValue = HistoryPageViewHistogram.GROUPED_MONTH;
         break;
       }
       break;
     }
     md_history.BrowserService.getInstance().recordHistogram('History.HistoryPageView', histogramValue, HistoryPageViewHistogram.END);
   }
 });