Desktop NTP metrics: Use ntp_tiles::metrics:: functions

components/ntp_tiles/most_visited_sites.cc

 // 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.
 
 #include "components/ntp_tiles/most_visited_sites.h"
 
 #include <algorithm>
 #include <set>
 #include <string>
 #include <utility>
@@ skipping 380 matching lines @@
   std::move(whitelist_tiles.begin(), whitelist_tiles.end(),
             std::back_inserter(merged_tiles));
   std::move(popular_tiles.begin(), popular_tiles.end(),
             std::back_inserter(merged_tiles));
   return merged_tiles;
 }
 
 void MostVisitedSites::NotifyMostVisitedURLsObserver() {
   if (!waiting_for_most_visited_sites_ && !waiting_for_popular_sites_ &&
       !recorded_impressions_) {
-    metrics::RecordImpressions(current_tiles_);
+    // TODO(treib): Move this out of here. crbug.com/514752
+    int num_tiles = static_cast<int>(current_tiles_.size());

[sfiera, 2016/10/25 12:12:11]

Why not "size_t num_tiles", "size_t i"?

[Marc Treib, 2016/10/25 12:23:39]

Then I'll have to cast below, since RecordTileImpression wants an int for the
index (as it should IMO - we don't generally use size_t or unsigned types in
general).

+    for (int i = 0; i < num_tiles; i++)
+      metrics::RecordTileImpression(i, current_tiles_[i].source);
+    metrics::RecordPageImpression(num_tiles);
     recorded_impressions_ = true;
   }
 
   if (!observer_)
     return;
 
   observer_->OnMostVisitedURLsAvailable(current_tiles_);
 }
 
 void MostVisitedSites::OnPopularSitesAvailable(bool success) {
@@ skipping 18 matching lines @@
 
 void MostVisitedSites::TopSitesChanged(TopSites* top_sites,
                                        ChangeReason change_reason) {
   if (mv_source_ == NTPTileSource::TOP_SITES) {
     // The displayed tiles are invalidated.
     InitiateTopSitesQuery();
   }
 }
 
 }  // namespace ntp_tiles