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

chrome/browser/resources/settings/search_page/search_page.js

Index: chrome/browser/resources/settings/search_page/search_page.js
diff --git a/chrome/browser/resources/settings/search_page/search_page.js b/chrome/browser/resources/settings/search_page/search_page.js
index 675730ba1462de360a42d39015c8f52ea1397338..01f0016cf2aa8566fe10aba79a439b7136624925 100644
--- a/chrome/browser/resources/settings/search_page/search_page.js
+++ b/chrome/browser/resources/settings/search_page/search_page.js
@@ -36,6 +36,9 @@ Polymer({
      * @private {!chrome.settingsPrivate.PrefObject|undefined}
      */
     hotwordSearchEnablePref_: Object,
+
+    /** @private */
+    googleNowAvailable_: Boolean,
   },
 
   /** @private {?settings.SearchEnginesBrowserProxy} */
@@ -61,6 +64,14 @@ Polymer({
     this.browserProxy_.getHotwordInfo().then(function(hotwordInfo) {
       this.hotwordInfoUpdate_(hotwordInfo);
     }.bind(this));
+
+    // Google Now cards in the launcher
+    cr.addWebUIListener(
+        'google-now-availability-changed',
+        this.googleNowAvailabilityUpdate_.bind(this));
+    this.browserProxy_.getGoogleNowAvailability().then(function(available) {
+        this.googleNowAvailabilityUpdate_(available);
+    }.bind(this));
   },
 
   /** @private */
@@ -104,6 +115,14 @@ Polymer({
   },
 
   /**
+   * @param {boolean} available
+   * @private
+   */
+  googleNowAvailabilityUpdate_: function(available) {
+    this.googleNowAvailable_ = available;
+  },
+
+  /**
    * @return {string}
    * @private
    */