Cleanup FWL Event and Message code.

xfa/fwl/core/cfwl_spinbutton.h

Index: xfa/fwl/core/cfwl_spinbutton.h
diff --git a/xfa/fwl/core/cfwl_spinbutton.h b/xfa/fwl/core/cfwl_spinbutton.h
index 6b53e68a9096df8dced8a5662753ec89eb8ff614..391d55c3e8e9992e8cc00301dd4fe5396603d23d 100644
--- a/xfa/fwl/core/cfwl_spinbutton.h
+++ b/xfa/fwl/core/cfwl_spinbutton.h
@@ -9,7 +9,6 @@
 
 #include <memory>
 
-#include "xfa/fwl/core/cfwl_event.h"
 #include "xfa/fwl/core/cfwl_timer.h"
 #include "xfa/fwl/core/cfwl_widget.h"
 #include "xfa/fxfa/cxfa_eventparam.h"
@@ -33,7 +32,6 @@ class CFWL_SpinButton : public CFWL_Widget {
   void DrawWidget(CFX_Graphics* pGraphics,
                   const CFX_Matrix* pMatrix = nullptr) override;
   void OnProcessMessage(CFWL_Message* pMessage) override;
-  void OnProcessEvent(CFWL_Event* pEvent) override;
   void OnDrawWidget(CFX_Graphics* pGraphics,
                     const CFX_Matrix* pMatrix) override;