RemoteContentSuggestions: Stores the time of the last successful background fetch in a pref

components/ntp_snippets/remote/remote_suggestions_provider.h

 // Copyright 2015 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 COMPONENTS_NTP_SNIPPETS_REMOTE_REMOTE_SUGGESTIONS_PROVIDER_H_
 #define COMPONENTS_NTP_SNIPPETS_REMOTE_REMOTE_SUGGESTIONS_PROVIDER_H_
 
 #include <cstddef>
 #include <deque>
 #include <map>
@@ skipping 133 matching lines @@
   const NTPSnippet::PtrVector& GetSnippetsForTesting(Category category) const {
     return category_contents_.find(category)->second.snippets;
   }
 
   // Dismissed snippets, only for unit tests.
   const NTPSnippet::PtrVector& GetDismissedSnippetsForTesting(
       Category category) const {
     return category_contents_.find(category)->second.dismissed;
   }
 
+  // Overrides internal clock for testing purposes.
+  void SetTickClockForTesting(std::unique_ptr<base::TickClock> tick_clock) {
+    tick_clock_ = std::move(tick_clock);

[tschumann, 2016/12/08 18:18:51]

nit: Couldn't we dependency-inject this into the constructor instead?
ForTesting() functions have a certain smell.

+  }
+
  private:
   friend class RemoteSuggestionsProviderTest;
 
   FRIEND_TEST_ALL_PREFIXES(RemoteSuggestionsProviderTest,
                            DontNotifyIfNotAvailable);
   FRIEND_TEST_ALL_PREFIXES(RemoteSuggestionsProviderTest,
                            RemoveExpiredDismissedContent);
   FRIEND_TEST_ALL_PREFIXES(RemoteSuggestionsProviderTest,
                            RescheduleOnStateChange);
   FRIEND_TEST_ALL_PREFIXES(RemoteSuggestionsProviderTest, StatusChanges);
@@ skipping 90 matching lines @@
   void OnImageDataFetched(const std::string& id_within_category,
                           const std::string& image_data) override;
 
   // Callbacks for the RemoteSuggestionsDatabase.
   void OnDatabaseLoaded(NTPSnippet::PtrVector snippets);
   void OnDatabaseError();
 
   // Callback for fetch-more requests with the NTPSnippetsFetcher.
   void OnFetchMoreFinished(
       const FetchDoneCallback& fetching_callback,
+      NTPSnippetsFetcher::FetchResult fetch_result,
       NTPSnippetsFetcher::OptionalFetchedCategories fetched_categories);
 
   // Callback for regular fetch requests with the NTPSnippetsFetcher.
   void OnFetchFinished(
+      bool interactive_request,
+      NTPSnippetsFetcher::FetchResult fetch_status,
       NTPSnippetsFetcher::OptionalFetchedCategories fetched_categories);
 
   // Moves all snippets from |to_archive| into the archive of the |content|.
   // Clears |to_archive|. As the archive is a FIFO buffer of limited size, this
   // function will also delete images from the database in case the associated
   // snippet gets evicted from the archive.
   void ArchiveSnippets(CategoryContent* content,
                        NTPSnippet::PtrVector* to_archive);
 
   // Sanitizes newly fetched snippets -- e.g. adding missing dates and filtering
@@ skipping 122 matching lines @@
   bool fetch_when_ready_;
 
   // Set to true if NukeAllSnippets is called while the service isn't ready.
   // The nuke will be executed once the service finishes initialization or
   // enters the READY state.
   bool nuke_when_initialized_;
 
   // Request throttler for limiting requests to thumbnail images.
   RequestThrottler thumbnail_requests_throttler_;
 
+  // A clock for getting the time. This allows to inject a tick clock in tests.
+  std::unique_ptr<base::TickClock> tick_clock_;
+
   DISALLOW_COPY_AND_ASSIGN(RemoteSuggestionsProvider);
 };
 
 }  // namespace ntp_snippets
 
 #endif  // COMPONENTS_NTP_SNIPPETS_REMOTE_REMOTE_SUGGESTIONS_PROVIDER_H_