Use UMA_HISTOGRAM_ENUMERATION instead of UMA_HISTOGRAM_BOOLEAN

chrome/browser/resources/ntp4/new_tab.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.
 
 /**
  * @fileoverview New tab page
  * This is the main code for the new tab page used by touch-enabled Chrome
  * browsers.  For now this is still a prototype.
  */
 
@@ skipping 209 matching lines @@
     chrome.send('initializeSyncLogin');
 
     doWhenAllSectionsReady(function() {
       // Tell the slider about the pages.
       newTabView.updateSliderCards();
       // Mark the current page.
       newTabView.cardSlider.currentCardValue.navigationDot.classList.add(
           'selected');
 
       if (loadTimeData.valueExists('notificationPromoText')) {
-        var promo = loadTimeData.getString('notificationPromoText');
+        var promoText = loadTimeData.getString('notificationPromoText');
         var tags = ['IMG'];
         var attrs = {
           src: function(node, value) {
             return node.tagName == 'IMG' &&
                    /^data\:image\/(?:png|gif|jpe?g)/.test(value);
           },
         };
-        showNotification(parseHtmlSubset(promo, tags, attrs), [], function() {
+
+        var promo = parseHtmlSubset(promoText, tags, attrs);
+        var promoLink = promo.querySelector('a');
+        if (promoLink) {
+          promoLink.addEventListener('click', function(e) {
+            chrome.send('notificationPromoLinkClicked');
+          });
+        }
+
+        showNotification(promo, [], function() {
           chrome.send('notificationPromoClosed');
         }, 60000);
         chrome.send('notificationPromoViewed');
       }
 
       cr.dispatchSimpleEvent(document, 'ntpLoaded', true, true);
       document.documentElement.classList.remove('starting-up');
 
       startTime = Date.now();
     });
@@ skipping 384 matching lines @@
     setFaviconDominantColor: setFaviconDominantColor,
     showNotification: showNotification,
     themeChanged: themeChanged,
     updateLogin: updateLogin
   };
 });
 
 document.addEventListener('DOMContentLoaded', ntp.onLoad);
 
 var toCssPx = cr.ui.toCssPx;