replace OVERRIDE and FINAL with override and final in chrome/browser/[a-i]*

chrome/browser/history/in_memory_history_backend.h

Index: chrome/browser/history/in_memory_history_backend.h
diff --git a/chrome/browser/history/in_memory_history_backend.h b/chrome/browser/history/in_memory_history_backend.h
index 846c9195e669aeeb0003063ab99577ec6ca7065d..1699834922a9a09e2b7f398569ab32125f3f6843 100644
--- a/chrome/browser/history/in_memory_history_backend.h
+++ b/chrome/browser/history/in_memory_history_backend.h
@@ -72,7 +72,7 @@ class InMemoryHistoryBackend : public content::NotificationObserver {
   // Notification callback.
   virtual void Observe(int type,
                        const content::NotificationSource& source,
-                       const content::NotificationDetails& details) OVERRIDE;
+                       const content::NotificationDetails& details) override;
 
  private:
   FRIEND_TEST_ALL_PREFIXES(HistoryBackendTest, DeleteAll);