[Media Router] Conditionally enable mDNS on Windows.

extensions/renderer/resources/media_router_bindings.js

 // Copyright 2015 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 mediaRouter;
 
 define('media_router_bindings', [
     'mojo/public/js/bindings',
     'mojo/public/js/core',
     'content/public/renderer/service_provider',
@@ skipping 455 matching lines @@
 
     /**
      * @type {function()}
      */
     this.stopObservingMediaRoutes = null;
 
     /**
      * @type {function()}
      */
     this.connectRouteByRouteId = null;
+
+    /**
+     * @type {function()}
+     */
+    this.enableMdnsDiscovery = null;
   };
 
   /**
    * Routes calls from Media Router to the provider manager extension.
    * Registered with the MediaRouter stub.
    * @param {!MediaRouter} MediaRouter proxy to call into the
    * Media Router mojo interface.
    * @constructor
    */
   function MediaRouteProvider(mediaRouter) {
@@ skipping 27 matching lines @@
       'sendRouteMessage',
       'sendRouteBinaryMessage',
       'listenForRouteMessages',
       'stopListeningForRouteMessages',
       'detachRoute',
       'terminateRoute',
       'joinRoute',
       'createRoute',
       'stopObservingMediaSinks',
       'startObservingMediaRoutes',
-      'connectRouteByRouteId'
+      'connectRouteByRouteId',
+      'enableMdnsDiscovery',
     ];
     requiredHandlers.forEach(function(nextHandler) {
       if (handlers[nextHandler] === undefined) {
         console.error(nextHandler + ' handler not registered.');
       }
     });
   }
 
   /**
    * Starts querying for sinks capable of displaying the media source
@@ skipping 199 matching lines @@
 
   /**
    * Requests that the provider manager stop sending information about active
    * media routes to the Media Router.
    * @param {!string} sourceUrn
    */
   MediaRouteProvider.prototype.stopObservingMediaRoutes = function(sourceUrn) {
     this.handlers_.stopObservingMediaRoutes(sourceUrn);
   };
 
+  /**
+   * Enables mDNS device discovery.
+   */
+  MediaRouteProvider.prototype.enableMdnsDiscovery = function() {
+    this.handlers_.enableMdnsDiscovery();
+  };
+
   mediaRouter = new MediaRouter(connector.bindHandleToProxy(
       serviceProvider.connectToService(
           mediaRouterMojom.MediaRouter.name),
       mediaRouterMojom.MediaRouter));
 
   return mediaRouter;
 });