ntp_tiles: Add tests covering tile-fetching logic

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>
 
 #include "base/callback.h"
 #include "base/feature_list.h"
 #include "base/strings/utf_string_conversions.h"
 #include "components/history/core/browser/top_sites.h"
 #include "components/ntp_tiles/constants.h"
 #include "components/ntp_tiles/field_trial.h"
 #include "components/ntp_tiles/icon_cacher.h"
 #include "components/ntp_tiles/pref_names.h"
 #include "components/ntp_tiles/switches.h"
-#include "components/pref_registry/pref_registry_syncable.h"
+#include "components/prefs/pref_registry_simple.h"

[Marc Treib, 2016/12/19 09:11:50]

Nice! Once we do the same for PopularSites, we can probably remove the
dependency on components/pref_registry :)

[mastiz, 2017/01/09 10:40:58]

sfiera@ raised some concerns so I reverted this change :-/

 #include "components/prefs/pref_service.h"
 
 using history::TopSites;
 using suggestions::ChromeSuggestion;
 using suggestions::SuggestionsProfile;
 using suggestions::SuggestionsService;
 
 namespace ntp_tiles {
 
 namespace {
@@ skipping 114 matching lines @@
   if (mv_source_ == NTPTileSource::SUGGESTIONS_SERVICE) {
     suggestions_service_->ClearBlacklist();
   }
 }
 
 void MostVisitedSites::OnBlockedSitesChanged() {
   BuildCurrentTiles();
 }
 
 // static
-void MostVisitedSites::RegisterProfilePrefs(
-    user_prefs::PrefRegistrySyncable* registry) {
+void MostVisitedSites::RegisterProfilePrefs(PrefRegistrySimple* registry) {
   registry->RegisterIntegerPref(prefs::kNumPersonalTiles, 0);
 }
 
 void MostVisitedSites::BuildCurrentTiles() {
   // Get the current suggestions from cache. If the cache is empty, this will
   // fall back to TopSites.
   OnSuggestionsProfileAvailable(
       suggestions_service_->GetSuggestionsDataFromCache().value_or(
           SuggestionsProfile()));
 }
@@ skipping 12 matching lines @@
     for (const auto& whitelist : supervisor_->whitelists()) {
       if (AreURLsEquivalent(whitelist.entry_point, url))
         return whitelist.large_icon_path;
     }
   }
   return base::FilePath();
 }
 
 void MostVisitedSites::OnMostVisitedURLsAvailable(
     const history::MostVisitedURLList& visited_list) {
+  // TODO(mastiz): Verify if suggestion service results have been fetched in
+  // the meantime, and if that's the case ignore this event.
   NTPTilesVector tiles;
   size_t num_tiles =
       std::min(visited_list.size(), static_cast<size_t>(num_sites_));
   for (size_t i = 0; i < num_tiles; ++i) {
     const history::MostVisitedURL& visited = visited_list[i];
     if (visited.url.is_empty()) {
       num_tiles = i;
       break;  // This is the signal that there are no more real visited sites.
     }
     if (supervisor_ && supervisor_->IsBlocked(visited.url))
@@ skipping 202 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