[Suggestions Service] Add support for expiring the SuggestionsStore

components/suggestions/suggestions_service.h

Index: components/suggestions/suggestions_service.h
diff --git a/components/suggestions/suggestions_service.h b/components/suggestions/suggestions_service.h
index ee1ed92ca6afa4f288d455684c805d8aef3cb87b..fee348502ee7a63c50c2874ae0a217acb2648de4 100644
--- a/components/suggestions/suggestions_service.h
+++ b/components/suggestions/suggestions_service.h
@@ -92,6 +92,12 @@ class SuggestionsService : public KeyedService, public net::URLFetcherDelegate {
   // Register SuggestionsService related prefs in the Profile prefs.
   static void RegisterProfilePrefs(user_prefs::PrefRegistrySyncable* registry);
 
+  // Sets default timestamp for suggestions which do not have expiry timestamp

[Mathieu, 2014/08/04 14:39:10]

Period at the end of comment.

[gayane -on leave until 09-2017, 2014/08/04 16:34:58]

Done.

+  void SetDefaultExpiryTimestamps(SuggestionsProfile* suggestions,
+      int64 timestamp_usec);
+
+  static const int64 default_expiry_usec = 72 *

[Mathieu, 2014/08/04 14:39:10]

naming style dictates kConstantName

[Mathieu, 2014/08/04 14:39:10]

this constant should be declared above (similar to the field trial constants),
and defined in the .cc

[gayane -on leave until 09-2017, 2014/08/04 16:34:57]

Done.

[gayane -on leave until 09-2017, 2014/08/04 16:34:58]

Done.

+      base::Time::kMicrosecondsPerHour;
  private:
   FRIEND_TEST_ALL_PREFIXES(SuggestionsServiceTest, BlacklistURLFails);
   FRIEND_TEST_ALL_PREFIXES(SuggestionsServiceTest, FetchSuggestionsData);