Popular sites on the NTP: Extend UMA histograms that track clicks and impressions

chrome/browser/android/most_visited_sites.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_ANDROID_MOST_VISITED_SITES_H_
 #define CHROME_BROWSER_ANDROID_MOST_VISITED_SITES_H_
 
 #include <jni.h>
 
 #include <string>
@@ skipping 61 matching lines @@
   // Callback for when data is available from TopSites.
   void OnMostVisitedURLsAvailable(
       const history::MostVisitedURLList& visited_list);
 
   // Callback for when data is available from the SuggestionsService.
   void OnSuggestionsProfileAvailable(
       const suggestions::SuggestionsProfile& suggestions_profile);
 
   // Adds the suggestions from |popular_sites_| into |titles| and |urls|. This
   // might reorder |titles| and |urls| to retain the absolute positions of the
-  // popular suggestions.
+  // popular suggestions. Also updates |tile_sources_| accordingly.
   void AddPopularSites(std::vector<base::string16>* titles,
-                       std::vector<std::string>* urls) const;
+                       std::vector<std::string>* urls);
 
   // Workhorse for AddPopularSites above. Implemented as a separate static
   // method for ease of testing.
   static void AddPopularSitesImpl(
       int num_sites,
       std::vector<base::string16>* titles,
       std::vector<std::string>* urls,
+      std::vector<std::string>* tile_sources,
       const std::vector<base::string16>& popular_titles,
       const std::vector<std::string>& popular_urls);
 
   // Notify the Java side observer about the availability of Most Visited Urls.
   void NotifyMostVisitedURLsObserver(const std::vector<base::string16>& titles,
                                      const std::vector<std::string>& urls);
 
   void OnPopularSitesAvailable(bool success);
 
   // Runs on the UI Thread.
   void OnLocalThumbnailFetched(
       const GURL& url,
       scoped_ptr<base::android::ScopedJavaGlobalRef<jobject>> j_callback,
       scoped_ptr<SkBitmap> bitmap);
 
   // Callback for when the thumbnail lookup is complete.
   // Runs on the UI Thread.
   void OnObtainedThumbnail(
       bool is_local_thumbnail,
       scoped_ptr<base::android::ScopedJavaGlobalRef<jobject>> j_callback,
       const GURL& url,
       const SkBitmap* bitmap);
 
-  // Records specific UMA histogram metrics.
-  void RecordUMAMetrics();
+  // Records thumbnail-related UMA histogram metrics.
+  void RecordThumbnailUMAMetrics();
+
+  // Records UMA histogram metrics related to the number of impressions.
+  void RecordImpressionUMAMetrics();
 
   // history::TopSitesObserver implementation.
   void TopSitesLoaded(history::TopSites* top_sites) override;
   void TopSitesChanged(history::TopSites* top_sites,
                        ChangeReason change_reason) override;
 
   // The profile whose most visited sites will be queried.
   Profile* profile_;
 
   // The observer to be notified when the list of most visited sites changes.
   base::android::ScopedJavaGlobalRef<jobject> observer_;
 
   // The maximum number of most visited sites to return.
   int num_sites_;
 
-  // Keeps track of whether the initial NTP load has been done.
-  bool initial_load_done_;
+  // Whether we have received an initial set of most visited sites (from either
+  // TopSites or the SuggestionsService).
+  bool received_most_visited_sites_;

[Bernhard Bauer, 2015/08/25 13:55:10]

Can you add an empty line before each comment?

[Marc Treib, 2015/08/25 14:13:23]

Done.

+  // Whether we have received the set of popular sites. Immediately set to true
+  // if popular sites are disabled.
+  bool received_popular_sites_;
+  // Whether we have recorded one-shot UMA metrics such as impressions. They are
+  // recorded once both the previous flags are true.
+  bool recorded_uma_;
 
   // Counters for UMA metrics.
 
   // Number of tiles using a local thumbnail image for this NTP session.
   int num_local_thumbs_;
   // Number of tiles for which a server thumbnail is provided.
   int num_server_thumbs_;
   // Number of tiles for which no thumbnail is found/specified.
   // In this case a gray tile is used as the main tile.
   int num_empty_thumbs_;
 
-  // Copy of the server suggestions (if enabled). Used for logging.
-  suggestions::SuggestionsProfile server_suggestions_;
+  // Identifier for where each tile came from (client, server, popular). Used
+  // for logging.
+  std::vector<std::string> tile_sources_;
 
   ScopedObserver<history::TopSites, history::TopSitesObserver> scoped_observer_;
 
   MostVisitedSource mv_source_;
 
   scoped_ptr<PopularSites> popular_sites_;
 
   // For callbacks may be run after destruction.
   base::WeakPtrFactory<MostVisitedSites> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(MostVisitedSites);
 };
 
 #endif  // CHROME_BROWSER_ANDROID_MOST_VISITED_SITES_H_