Move the message definitions to their own files.

xfa/fxfa/app/xfa_fftextedit.cpp

 // Copyright 2014 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
 
 #include "xfa/fxfa/app/xfa_fftextedit.h"
 
 #include <vector>
 
 #include "xfa/fwl/core/cfwl_datetimepicker.h"
 #include "xfa/fwl/core/cfwl_edit.h"
-#include "xfa/fwl/core/cfwl_message.h"
+#include "xfa/fwl/core/cfwl_msgkillfocus.h"
+#include "xfa/fwl/core/cfwl_msgmouse.h"
+#include "xfa/fwl/core/cfwl_msgsetfocus.h"
 #include "xfa/fwl/core/fwl_noteimp.h"
 #include "xfa/fwl/core/ifwl_edit.h"
 #include "xfa/fxfa/app/xfa_fffield.h"
 #include "xfa/fxfa/app/xfa_fwladapter.h"
 #include "xfa/fxfa/app/xfa_textlayout.h"
 #include "xfa/fxfa/cxfa_eventparam.h"
 #include "xfa/fxfa/parser/xfa_localevalue.h"
 #include "xfa/fxfa/xfa_ffapp.h"
 #include "xfa/fxfa/xfa_ffdoc.h"
 #include "xfa/fxfa/xfa_ffdocview.h"
@@ skipping 658 matching lines @@
 
 void CXFA_FFDateTimeEdit::OnProcessEvent(CFWL_Event* pEvent) {
   if (pEvent->GetClassID() == CFWL_EventType::SelectChanged) {
     CFWL_Event_DtpSelectChanged* event = (CFWL_Event_DtpSelectChanged*)pEvent;
     OnSelectChanged(m_pNormalWidget->GetWidget(), event->iYear, event->iMonth,
                     event->iDay);
     return;
   }
   CXFA_FFTextEdit::OnProcessEvent(pEvent);
 }