Reland "Propagate information about how ARC apps are launched"

chrome/browser/resources/options/browser_options.js

 // Copyright (c) 2012 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.
 
 cr.exportPath('options');
 
 /**
  * @typedef {{actionLinkText: (string|undefined),
  *            accountInfo: (string|undefined),
  *            childUser: (boolean|undefined),
@@ skipping 852 matching lines @@
           var androidAppSettings = $('android-apps-settings');
           if (androidAppSettings != null)
             androidAppSettings.hidden = isArcEnabled;
 
           var talkbackSettingsButton = $('talkback-settings-button');
           if (talkbackSettingsButton != null)
             talkbackSettingsButton.hidden = isArcEnabled;
         });
 
         $('android-apps-settings-link').addEventListener('click', function(e) {
-            chrome.send('showAndroidAppsSettings');
+            // MouseEvent.detail indicates the current click count (or tap
+            // count, in the case of touch events) in the 'click' event.
+            var activatedFromKeyboard = e.detail == 0;
+            chrome.send('showAndroidAppsSettings', [activatedFromKeyboard]);
         });
       }
     },
 
     /** @override */
     didShowPage: function() {
       $('search-field').focus();
     },
 
    /**
@@ skipping 1579 matching lines @@
 
       settings.hidden = !isVisible;
     };
   }
 
   // Export
   return {
     BrowserOptions: BrowserOptions
   };
 });