chrome: Use base::MessageLoop. (Part 3)

chrome/browser/history/history_backend.h

Index: chrome/browser/history/history_backend.h
diff --git a/chrome/browser/history/history_backend.h b/chrome/browser/history/history_backend.h
index d572e8ce19b8b879e1e9696a719bc1440d693b7b..0d848cdcbef3b7b4c1a404e925ac118ff3c1b240 100644
--- a/chrome/browser/history/history_backend.h
+++ b/chrome/browser/history/history_backend.h
@@ -474,7 +474,7 @@ class HistoryBackend : public base::RefCountedThreadSafe<HistoryBackend>,
   // Sets the task to run and the message loop to run it on when this object
   // is destroyed. See HistoryService::SetOnBackendDestroyTask for a more
   // complete description.
-  void SetOnBackendDestroyTask(MessageLoop* message_loop,
+  void SetOnBackendDestroyTask(base::MessageLoop* message_loop,
                                const base::Closure& task);
 
   // Adds the given rows to the database if it doesn't exist. A visit will be
@@ -866,7 +866,7 @@ class HistoryBackend : public base::RefCountedThreadSafe<HistoryBackend>,
   base::Time first_recorded_time_;
 
   // When set, this is the task that should be invoked on destruction.
-  MessageLoop* backend_destroy_message_loop_;
+  base::MessageLoop* backend_destroy_message_loop_;
   base::Closure backend_destroy_task_;
 
   // Tracks page transition types.