Merge IFWL and CFWL classes.

xfa/fwl/core/cfwl_message.h

 // Copyright 2016 PDFium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com
 
 #ifndef XFA_FWL_CORE_CFWL_MESSAGE_H_
 #define XFA_FWL_CORE_CFWL_MESSAGE_H_
 
 #include <memory>
 
 #include "core/fxcrt/fx_basic.h"
 #include "core/fxcrt/fx_string.h"
 #include "core/fxcrt/fx_system.h"
 #include "xfa/fwl/core/fwl_error.h"
 
 enum class CFWL_MessageType {
   None = 0,
   Key,
   KillFocus,
   Mouse,
   MouseWheel,
   SetFocus
 };
 
-class IFWL_Widget;
+class CFWL_Widget;
 
 class CFWL_Message {
  public:
   CFWL_Message();
   virtual ~CFWL_Message();
 
   virtual std::unique_ptr<CFWL_Message> Clone();
   virtual CFWL_MessageType GetClassID() const;
 
-  IFWL_Widget* m_pSrcTarget;
-  IFWL_Widget* m_pDstTarget;
+  CFWL_Widget* m_pSrcTarget;
+  CFWL_Widget* m_pDstTarget;
   uint32_t m_dwExtend;
 };
 
 
 #endif  // XFA_FWL_CORE_CFWL_MESSAGE_H_