Add OVERRIDE to chrome/browser/chromeos/.

chrome/browser/chromeos/notifications/system_notification.h

Index: chrome/browser/chromeos/notifications/system_notification.h
diff --git a/chrome/browser/chromeos/notifications/system_notification.h b/chrome/browser/chromeos/notifications/system_notification.h
index d140219781fb838aeccc176e4e0480fc1eef6c48..d7e0811c31c58c6a5c354b19f8b149ad91e0542e 100644
--- a/chrome/browser/chromeos/notifications/system_notification.h
+++ b/chrome/browser/chromeos/notifications/system_notification.h
@@ -8,6 +8,7 @@
 
 #include <string>
 
+#include "base/compiler_specific.h"
 #include "base/basictypes.h"
 #include "base/string16.h"
 #include "chrome/browser/chromeos/notifications/balloon_view_host.h"  // MessageCallback
@@ -66,11 +67,11 @@ class SystemNotification {
   class Delegate : public NotificationDelegate {
    public:
     explicit Delegate(const std::string& id);
-    virtual void Display() {}
-    virtual void Error() {}
-    virtual void Close(bool by_user) {}
-    virtual void Click() {}
-    virtual std::string id() const;
+    virtual void Display() OVERRIDE {}
+    virtual void Error() OVERRIDE {}
+    virtual void Close(bool by_user) OVERRIDE {}
+    virtual void Click() OVERRIDE {}
+    virtual std::string id() const OVERRIDE;
 
    private:
     std::string id_;