Most visited iframe now postMessage to signal the iframing page that the link has been displayed

chrome/browser/ui/webui/ntp/ntp_user_data_logger.h

 // Copyright 2013 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.
 
 #ifndef CHROME_BROWSER_UI_WEBUI_NTP_NTP_USER_DATA_LOGGER_H_
 #define CHROME_BROWSER_UI_WEBUI_NTP_NTP_USER_DATA_LOGGER_H_
 
 #include "chrome/common/ntp_logging_events.h"
 #include "content/public/browser/web_contents_observer.h"
 #include "content/public/browser/web_contents_user_data.h"
 
 namespace content {
 class WebContents;
 }
 
 // Helper class for logging data from the NTP. Attached to each NTP instance.
 class NTPUserDataLogger
     : public content::WebContentsObserver,
       public content::WebContentsUserData<NTPUserDataLogger> {
  public:
   virtual ~NTPUserDataLogger();
 
   static NTPUserDataLogger* GetOrCreateFromWebContents(
       content::WebContents* content);
 
-  // Logs the error percentage rate when loading thumbnail images for this NTP
-  // session to UMA histogram. Called when the user navigates to a URL. Only
-  // called for the instant NTP.
-  void EmitThumbnailErrorRate();
-
   // Logs a number of statistics regarding the NTP. Called when an NTP tab is
   // about to be deactivated (be it by switching tabs, losing focus or closing
   // the tab/shutting down Chrome), or when the user navigates to a URL.
   void EmitNtpStatistics();
 
   // Called each time an event occurs on the NTP that requires a counter to be
   // incremented.
   void LogEvent(NTPLoggingEventType event);
 
   // Logs an impression on one of the Most Visited tiles by a given provider.
   void LogImpression(int position, const base::string16& provider);
 
   // content::WebContentsObserver override
   virtual void NavigationEntryCommitted(
       const content::LoadCommittedDetails& load_details) OVERRIDE;
 
  protected:
   explicit NTPUserDataLogger(content::WebContents* contents);
 
-  // Returns the percent error given |events| occurrences and |errors| errors.
-  virtual size_t GetPercentError(size_t errors, size_t events) const;
-
  private:
   friend class content::WebContentsUserData<NTPUserDataLogger>;
 
-  // Total number of mouseovers for this NTP session.
-  size_t number_of_mouseovers_;
+  // True if at least one iframe came from a server-side suggestion. In
+  // practice, either all the iframes are server-side suggestions or none are.
+  bool server_side_suggestions_;

[Alexei Svitkine (slow), 2014/01/16 19:50:30]

Optional nit: I think has_server_side_suggestions_ would be a slightly better
name. Up to you.

[beaudoin, 2014/01/17 03:51:46]

Done.

 
-  // Total number of attempts made to load thumbnail images for this NTP
-  // session.
-  size_t number_of_thumbnail_attempts_;
+  // Total number of tiles rendered, no matter if it's a thumbnail, a gray tile
+  // or an external tile.
+  size_t number_of_tiles_;
+
+  // Total number of tiles using a local thumbnail image for this NTP session.
+  size_t number_of_thumbnail_tiles_;
+
+  // Total number of tiles for which no thumbnail is specified and a gray tile
+  // with the domain is used as the main tile.
+  size_t number_of_gray_tiles_;
+
+  // Total number of tiles for which the visual appearance is handled externally
+  // by the page itself.
+  size_t number_of_external_tiles_;
 
   // Total number of errors that occurred when trying to load thumbnail images
   // for this NTP session. When these errors occur a grey tile is shown instead
   // of a thumbnail image.
   size_t number_of_thumbnail_errors_;
 
-  // Total number of attempts made to load thumbnail images while providing a
-  // fallback thumbnail for this NTP session.
-  size_t number_of_fallback_thumbnails_requested_;
+  // The number of times a gray tile with the domain was used as the fallback
+  // for a failed thumbnail.
+  size_t number_of_gray_tile_fallbacks_;
 
-  // Total number of errors that occurred while trying to load the primary
-  // thumbnail image and that caused a fallback to the secondary thumbnail.
-  size_t number_of_fallback_thumbnails_used_;
+  // The number of times an external tile, for which the visual appearance is
+  // handled by the page itself, was the fallback for a failed thumbnail.
+  size_t number_of_external_tile_fallbacks_;
 
-  // Total number of tiles for which the visual appearance is handled externally
-  // by the page itself.
-  size_t number_of_external_tiles_;
-
-  // True if at least one iframe came from a server-side suggestion. In
-  // practice, either all the iframes are server-side suggestions or none are.
-  bool server_side_suggestions_;
+  // Total number of mouseovers for this NTP session.
+  size_t number_of_mouseovers_;
 
   // The URL of this New Tab Page - varies based on NTP version.
   GURL ntp_url_;
 
   DISALLOW_COPY_AND_ASSIGN(NTPUserDataLogger);
 };
 
 #endif  // CHROME_BROWSER_UI_WEBUI_NTP_NTP_USER_DATA_LOGGER_H_