Add pyauto hook for getting and manipulating the data underneath the NTP....

chrome/browser/history/top_sites.cc

Index: chrome/browser/history/top_sites.cc
===================================================================
--- chrome/browser/history/top_sites.cc	(revision 61074)
+++ chrome/browser/history/top_sites.cc	(working copy)
@@ -51,7 +51,8 @@
                                        migration_in_progress_(false),
                                        waiting_for_results_(true),
                                        blacklist_(NULL),
-                                       pinned_urls_(NULL) {
+                                       pinned_urls_(NULL),
+                                       handle_to_wait_for_(NULL) {
   if (!profile_)
     return;
 
@@ -90,7 +91,7 @@
 
   // Start the one-shot timer.
   timer_.Start(base::TimeDelta::FromSeconds(kUpdateIntervalSecs), this,
-               &TopSites::StartQueryForMostVisited);
+               &TopSites::TimerFired);
 }
 
 void TopSites::ReadDatabase() {
@@ -449,7 +450,7 @@
 
   timer_.Stop();
   timer_.Start(GetUpdateDelay(), this,
-               &TopSites::StartQueryForMostVisited);
+               &TopSites::TimerFired);
 }
 
 void TopSites::OnMigrationDone() {
@@ -638,23 +639,21 @@
   }
 }
 
-void TopSites::StartQueryForMostVisited() {
+CancelableRequestProvider::Handle TopSites::StartQueryForMostVisited() {
+  CancelableRequestProvider::Handle request_handle = NULL;
   if (mock_history_service_) {
     // Testing with a mockup.
     // QueryMostVisitedURLs is not virtual, so we have to duplicate the code.
-    mock_history_service_->QueryMostVisitedURLs(
+    request_handle = mock_history_service_->QueryMostVisitedURLs(
         kTopSitesNumber + blacklist_->size(),
         kDaysOfHistory,
         &cancelable_consumer_,
         NewCallback(this, &TopSites::OnTopSitesAvailable));
-  } else {
-    if (!profile_)
-      return;
-
+  } else if (profile_) {
     HistoryService* hs = profile_->GetHistoryService(Profile::EXPLICIT_ACCESS);
     // |hs| may be null during unit tests.
     if (hs) {
-      hs->QueryMostVisitedURLs(
+      request_handle = hs->QueryMostVisitedURLs(
           kTopSitesNumber + blacklist_->size(),
           kDaysOfHistory,
           &cancelable_consumer_,
@@ -663,8 +662,13 @@
       LOG(INFO) << "History Service not available.";
     }
   }
+  return request_handle;
 }
 
+void TopSites::TimerFired() {
+  StartQueryForMostVisited();
+}
+
 void TopSites::StartMigration() {
   LOG(INFO) << "Starting migration to TopSites.";
   migration_in_progress_ = true;
@@ -760,6 +764,19 @@
   }
 }
 
+void TopSites::RefreshAndCallback(CancelableRequestConsumer* consumer,
+                                  Callback0::Type* callback) {
+  if (refresh_callback_) {
+    DLOG(ERROR) << "Waiting for refresh before previous refresh finished";
+    return;
+  }
+  scoped_refptr<CancelableRequest<Callback0::Type> > request(
+      new CancelableRequest<Callback0::Type>(callback));
+  AddRequest(request, consumer);
+  refresh_callback_ = request;
+  handle_to_wait_for_ = StartQueryForMostVisited();
+}
+
 void TopSites::ClearProfile() {
   profile_ = NULL;
 }
@@ -781,6 +798,19 @@
   AddPrepopulatedPages(&pages);
   ChromeThread::PostTask(ChromeThread::DB, FROM_HERE, NewRunnableMethod(
       this, &TopSites::UpdateMostVisited, pages));
+
+  if (handle == handle_to_wait_for_) {
+    if (ChromeThread::IsWellKnownThread(ChromeThread::UI)) {
+      DCHECK(ChromeThread::CurrentlyOn(ChromeThread::UI));
+      // Posting this task after the one above should guarantee that
+      // |top_sites_| is completely refreshed.
+      ChromeThread::PostTask(ChromeThread::DB, FROM_HERE, NewRunnableMethod(
+          this, &TopSites::InvokeRefreshCallback));
+    } else {
+      // This will happen in unit tests when we don't have a real UI thread.
+      InvokeRefreshCallbackOnUIThread();
+    }
+  }
 }
 
 // static
@@ -893,4 +923,19 @@
   }
 }
 
+void TopSites::InvokeRefreshCallback() {
+  ChromeThread::PostTask(ChromeThread::UI, FROM_HERE,
+      NewRunnableMethod(this, &TopSites::InvokeRefreshCallbackOnUIThread));
+}
+
+void TopSites::InvokeRefreshCallbackOnUIThread() {
+  if (refresh_callback_) {
+    if (!refresh_callback_->canceled())
+      refresh_callback_->ForwardResult(Callback0::Type::TupleType());
+    refresh_callback_.release();
+  } else {
+    LOG(DFATAL) << "No refresh callback was set.";
+  }
+}
+
 }  // namespace history