Call scoped_refptr<T>::get() rather than relying on implicit "operator T*"

chrome/browser/history/top_sites_backend.cc

Index: chrome/browser/history/top_sites_backend.cc
diff --git a/chrome/browser/history/top_sites_backend.cc b/chrome/browser/history/top_sites_backend.cc
index e900cb57813b7aa9af043bf3ecb712c62a30c6f4..bdf589c75db27111ab2e31d2005813a86704cb43 100644
--- a/chrome/browser/history/top_sites_backend.cc
+++ b/chrome/browser/history/top_sites_backend.cc
@@ -41,10 +41,12 @@ void TopSitesBackend::GetMostVisitedThumbnails(
   bool* need_history_migration = new bool(false);
 
   tracker->PostTaskAndReply(
-      BrowserThread::GetMessageLoopProxyForThread(BrowserThread::DB),
+      BrowserThread::GetMessageLoopProxyForThread(BrowserThread::DB).get(),
       FROM_HERE,
       base::Bind(&TopSitesBackend::GetMostVisitedThumbnailsOnDBThread,
-                 this, thumbnails, need_history_migration),
+                 this,
+                 thumbnails,
+                 need_history_migration),
       base::Bind(callback, thumbnails, base::Owned(need_history_migration)));
 }
 
@@ -72,7 +74,7 @@ void TopSitesBackend::ResetDatabase() {
 void TopSitesBackend::DoEmptyRequest(const base::Closure& reply,
                                      CancelableTaskTracker* tracker) {
   tracker->PostTaskAndReply(
-      BrowserThread::GetMessageLoopProxyForThread(BrowserThread::DB),
+      BrowserThread::GetMessageLoopProxyForThread(BrowserThread::DB).get(),
       FROM_HERE,
       base::Bind(&base::DoNothing),
       reply);