PopularSites: don't wait for a SuggestionsService network request

chrome/browser/android/ntp/most_visited_sites.h

Index: chrome/browser/android/ntp/most_visited_sites.h
diff --git a/chrome/browser/android/ntp/most_visited_sites.h b/chrome/browser/android/ntp/most_visited_sites.h
index 467983b9438e5492d71d722b658d387c852b80b0..86b0927dc2a0ef955b1558709f490eeab1ef6941 100644
--- a/chrome/browser/android/ntp/most_visited_sites.h
+++ b/chrome/browser/android/ntp/most_visited_sites.h
@@ -89,9 +89,9 @@ class MostVisitedSites : public history::TopSitesObserver,
 
   ~MostVisitedSites() override;
 
-  // Does not take ownership of |observer|, which must outlive this object.
-  void SetMostVisitedURLsObserver(
-      Observer* observer, int num_sites);
+  // Does not take ownership of |observer|, which must outlive this object and
+  // must not be null.

[Bernhard Bauer, 2016/04/29 14:15:31]

From a general API POV, this seems a bit problematic, because if the observer
should be destroyed before this object is, it couldn't be unregistered. We can
deal with that if and when it should arise though.

[Marc Treib, 2016/04/29 14:18:57]

True, but I'm really just documenting the pre-existing assumption here.

+  void SetMostVisitedURLsObserver(Observer* observer, int num_sites);
 
   using ThumbnailCallback = base::Callback<
       void(bool /* is_local_thumbnail */, const SkBitmap* /* bitmap */)>;
@@ -111,7 +111,7 @@ class MostVisitedSites : public history::TopSitesObserver,
   // TODO(treib): use SuggestionsVector in internal functions. crbug.com/601734
   using SuggestionsPtrVector = std::vector<std::unique_ptr<Suggestion>>;
 
-  void QueryMostVisitedURLs();
+  void BuildCurrentSuggestions();
 
   // Initialize the query to Top Sites. Called if the SuggestionsService is not
   // enabled, or if it returns no data.