Adds the MostVisitedAction stat. This stat will provide a baseline to compare

chrome/browser/resources/ntp4/most_visited_page.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.
 
 cr.define('ntp', function() {
   'use strict';
 
   var TilePage = ntp.TilePage;
 
   /**
+   * See description for these values in ntp_stats.h.
+   * @enum {number}
+   */
+  var NtpFollowAction = {
+    CLICKED_TILE: 11,
+    CLICKED_OTHER_NTP_PANE: 12,
+    OTHER: 13
+  };
+
+  /**
    * A counter for generating unique tile IDs.
    */
   var tileID = 0;
 
   /**
    * Creates a new Most Visited object for tiling.
    * @constructor
    * @extends {HTMLAnchorElement}
    */
   function MostVisited() {
@@ skipping 113 matching lines @@
         // Records an app launch from the most visited page (Chrome will decide
         // whether the url is an app). TODO(estade): this only works for clicks;
         // other actions like "open in new tab" from the context menu won't be
         // recorded. Can this be fixed?
         chrome.send('recordAppLaunchByURL',
                     [encodeURIComponent(this.href),
                      ntp.APP_LAUNCH.NTP_MOST_VISITED]);
         // Records the index of this tile.
         chrome.send('metricsHandler:recordInHistogram',
                     ['NewTabPage.MostVisited', this.index, 8]);
+        chrome.send('mostVisitedAction',
+                    [NtpFollowAction.CLICKED_TILE]);
       }
     },
 
     /**
      * Allow blacklisting most visited site using the keyboard.
      */
     handleKeyDown_: function(e) {
       if (!cr.isMac && e.keyCode == 46 || // Del
           cr.isMac && e.metaKey && e.keyCode == 8) { // Cmd + Backspace
         this.blacklist_();
@@ skipping 128 matching lines @@
     return el;
   }
 
   MostVisitedPage.prototype = {
     __proto__: TilePage.prototype,
 
     initialize: function() {
       this.classList.add('most-visited-page');
       this.data_ = null;
       this.mostVisitedTiles_ = this.getElementsByClassName('most-visited real');
+
+      this.addEventListener('carddeselected', this.handleCardDeselected_);
+      this.addEventListener('cardselected', this.handleCardSelected_);
     },
 
     /**
      * Create blank (filler) tiles.
      * @private
      */
     createTiles_: function() {
       for (var i = 0; i < THUMBNAIL_COUNT; i++) {
         this.appendTile(new MostVisited());
       }
     },
 
     /**
      * Update the tiles after a change to |data_|.
      */
     updateTiles_: function() {
       for (var i = 0; i < THUMBNAIL_COUNT; i++) {
         var page = this.data_[i];
         var tile = this.mostVisitedTiles_[i];
 
         if (i >= this.data_.length)
           tile.reset();
         else
           tile.updateForData(page);
       }
     },
 
     /**
+     * Handles the 'card deselected' event (i.e. the user clicked to another
+     * pane).
+     * @param {Event} e The CardChanged event.
+     */
+    handleCardDeselected_: function(e) {
+      if (!document.documentElement.classList.contains('starting-up')) {
+        chrome.send('mostVisitedAction',
+                    [NtpFollowAction.CLICKED_OTHER_NTP_PANE]);
+      }
+    },
+
+    /**
+     * Handles the 'card selected' event (i.e. the user clicked to select the
+     * Most Visited pane).
+     * @param {Event} e The CardChanged event.
+     */
+    handleCardSelected_: function(e) {
+      if (!document.documentElement.classList.contains('starting-up')) {
+        chrome.send('mostVisitedSelected');
+      }
+    },
+
+    /**
      * Array of most visited data objects.
      * @type {Array}
      */
     get data() {
       return this.data_;
     },
     set data(data) {
       var startTime = Date.now();
 
       // The first time data is set, create the tiles.
       if (!this.data_) {
         this.createTiles_();
         this.data_ = data.slice(0, THUMBNAIL_COUNT);
       } else {
         this.data_ = refreshData(this.data_, data);
       }
 
       this.updateTiles_();
       logEvent('mostVisited.layout: ' + (Date.now() - startTime));
     },
 
     /** @inheritDoc */
     shouldAcceptDrag: function(e) {
       return false;
     },
 
+    /**
+     * Executed once the NTP has loaded. Checks if the Most Visited pane is
+     * shown or not.
+     */
+    onLoaded: function() {
+      if (ntp.getCardSlider() && ntp.getCardSlider().currentCardValue) {
+        if (ntp.getCardSlider().currentCardValue.classList
+            .contains('most-visited-page')) {
+          chrome.send('mostVisitedSelected');
+        }
+      }
+    },
+
     /** @inheritDoc */
     heightForWidth: heightForWidth,
   };
 
   /**
    * We've gotten additional Most Visited data. Update our old data with the
    * new data. The ordering of the new data is not important, except when a
    * page is pinned. Thus we try to minimize re-ordering.
    * @param {Array} oldData The current Most Visited page list.
    * @param {Array} newData The new Most Visited page list.
@@ skipping 61 matching lines @@
     }
 
     return oldData;
   };
 
   return {
     MostVisitedPage: MostVisitedPage,
     refreshData: refreshData,
   };
 });
+
+document.addEventListener('ntploaded', ntp.MostVisitedPage.prototype.onLoaded);