MD Settings: Add "Show Google Now cards in the launcher" row in Search section.

chrome/browser/resources/settings/search_engines_page/search_engines_browser_proxy.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.
 
 /**
  * @fileoverview A helper object used from the "Manage search engines" section
  * to interact with the browser.
  */
 
 /**
@@ skipping 69 matching lines @@
      * @param {string} fieldValue
      * @return {!Promise<boolean>}
      */
     validateSearchEngineInput: function(fieldName, fieldValue) {},
 
     /** @return {!Promise<!SearchPageHotwordInfo>} */
     getHotwordInfo: function() {},
 
     /** @param {boolean} enabled */
     setHotwordSearchEnabled: function(enabled) {},
+
+    /** @return {!Promise<boolean>} */
+    getGoogleNowAvailability() {},
   };
 
   /**
    * @constructor
    * @implements {settings.SearchEnginesBrowserProxy}
    */
   function SearchEnginesBrowserProxyImpl() {}
   // The singleton instance_ is replaced with a test version of this wrapper
   // during testing.
   cr.addSingletonGetter(SearchEnginesBrowserProxyImpl);
@@ skipping 39 matching lines @@
 
     /** @override */
     getHotwordInfo: function() {
       return cr.sendWithPromise('getHotwordInfo');
     },
 
     /** @override */
     setHotwordSearchEnabled: function(enabled) {
       chrome.send('setHotwordSearchEnabled', [enabled]);
     },
+
+    /** @override */
+    getGoogleNowAvailability: function() {
+      return cr.sendWithPromise('getGoogleNowAvailability');
+    },
   };
 
   return {
     SearchEnginesBrowserProxy: SearchEnginesBrowserProxy,
     SearchEnginesBrowserProxyImpl: SearchEnginesBrowserProxyImpl,
   };
 });