Refactor Timer classes in preparation for landing FrameTimers.

third_party/WebKit/Source/web/ExternalPopupMenu.h

 /*
  * Copyright (C) 2010 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 62 matching lines @@
     void updateFromElement(UpdateReason) override;
     void disconnectClient() override;
 
     // WebExternalPopupClient methods:
     void didChangeSelection(int index) override;
     void didAcceptIndex(int index) override;
     void didAcceptIndices(const WebVector<int>& indices) override;
     void didCancel() override;
 
     bool showInternal();
-    void dispatchEvent(Timer<ExternalPopupMenu>*);
+    void dispatchEvent(TimerBase*);
     void update();
 
     Member<HTMLSelectElement> m_ownerElement;
     Member<LocalFrame> m_localFrame;
     WebViewImpl& m_webView;
     std::unique_ptr<WebMouseEvent> m_syntheticEvent;
     Timer<ExternalPopupMenu> m_dispatchEventTimer;
     // The actual implementor of the show menu.
     WebExternalPopupMenu* m_webExternalPopupMenu;
     bool m_needsUpdate = false;
 };
 
 } // namespace blink
 
 #endif // ExternalPopupMenu_h