Make ThumbnailStore broadcast a notification when it has finished reading thumbnails from disk.

Make DOMUIThumbnailSource wait for this notification if ThumbnailStore isn't ready yet.
Also clean up some of the code.

Review URL: http://codereview.chromium.org/155911

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@21785 0039d316-1c4b-4281-b951-d872f2087c98

2 files changed, 9 insertions, 6 deletions

diff --git a/chrome/browser/history/history.h b/chrome/browser/history/history.h
index 9aec250..0643139 100644
--- a/chrome/browser/history/history.h
+++ b/chrome/browser/history/history.h
@@ -306,7 +306,10 @@ class HistoryService : public CancelableRequestProvider,
   // in the map containing redirects from the URL.  For example, if we have the
   // redirect chain A -> B -> C and A is a top visited URL, then A will be in
   // the vector and "A => {B -> C}" will be in the map.
-  typedef Callback2<std::vector<GURL>*, history::RedirectMap*>::Type
+  typedef Callback4<Handle,
+                    bool,  // Did we get the top urls and redirects?
+                    std::vector<GURL>*,  // List of top URLs.
+                    history::RedirectMap*>::Type  // Redirects for top URLs.
       QueryTopURLsAndRedirectsCallback;
 
   // Request the top |result_count| most visited URLs and the chain of redirects
diff --git a/chrome/browser/history/history_backend.cc b/chrome/browser/history/history_backend.cc
index bdf2351..1ccd7cf 100644
--- a/chrome/browser/history/history_backend.cc
+++ b/chrome/browser/history/history_backend.cc
@@ -1163,7 +1163,7 @@ void HistoryBackend::QueryTopURLsAndRedirects(
 
   if (!db_.get()) {
     request->ForwardResult(QueryTopURLsAndRedirectsRequest::TupleType(
-        NULL, NULL));
+        request->handle(), false, NULL, NULL));
     return;
   }
 
@@ -1176,13 +1176,13 @@ void HistoryBackend::QueryTopURLsAndRedirects(
 
   for (size_t i = 0; i < data.size(); ++i) {
     top_urls->push_back(data[i]->GetURL());
-    history::RedirectList list;
-    GetMostRecentRedirectsFrom(top_urls->back(), &list);
-    (*redirects)[top_urls->back()] = new RefCountedVector<GURL>(list);
+    RefCountedVector<GURL>* list = new RefCountedVector<GURL>;
+    GetMostRecentRedirectsFrom(top_urls->back(), &list->data);
+    (*redirects)[top_urls->back()] = list;
   }
 
   request->ForwardResult(QueryTopURLsAndRedirectsRequest::TupleType(
-      top_urls, redirects));
+      request->handle(), true, top_urls, redirects));
 }
 
 void HistoryBackend::GetRedirectsFromSpecificVisit(