Control visibility of 2D VR menu buttons using native state.

chrome/browser/resources/vr_shell/vr_shell_ui_api.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.
 
 var api = (function() {
   'use strict';
 
   /**
    * Enumeration of scene update commands.
    * @enum {number}
@@ skipping 52 matching lines @@
   /**
    * Enumeration of actions that can be triggered by the HTML UI.
    * @enum {number}
    * @const
    */
   var Action = Object.freeze({
     'HISTORY_BACK': 0,
     'HISTORY_FORWARD': 1,
     'RELOAD': 2,
     'ZOOM_OUT': 3,
-    'ZOOM_IN': 4,
+    'ZOOM_IN': 4
   });
 
   /**
+   * Enumeration of modes that can be specified by the native side.
+   * @enum {number}
+   * @const
+   */
+  var Mode = Object.freeze({
+    'UNKNOWN': -1,
+    'STANDARD': 0,
+    'WEB_VR': 1
+  });
+
+  /**
    * Triggers an Action.
    */
   function doAction(action) {
     chrome.send('doAction', [action]);
   }
 
   /**
    * Notify native scene management that DOM loading has completed, at the
    * specified page size.
    */
@@ skipping 174 matching lines @@
   };
 
   return {
     sendCommands: sendCommands,
     XAnchoring: XAnchoring,
     YAnchoring: YAnchoring,
     Property: Property,
     Easing: Easing,
     Command: Command,
     Action: Action,
+    Mode: Mode,
     getContentElementId: getContentElementId,
     UiElement: UiElement,
     UiElementUpdate: UiElementUpdate,
     Animation: Animation,
     doAction: doAction,
     domLoaded: domLoaded,
   };
 })();