Move the message definitions to their own files.

xfa/fwl/core/ifwl_comboboxproxy.cpp

 // 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
 
 #include "xfa/fwl/core/ifwl_comboboxproxy.h"
 
+#include "xfa/fwl/core/cfwl_msgkillfocus.h"
+#include "xfa/fwl/core/cfwl_msgmouse.h"
 #include "xfa/fwl/core/fwl_noteimp.h"
 #include "xfa/fwl/core/ifwl_app.h"
 #include "xfa/fwl/core/ifwl_combobox.h"
 
 IFWL_ComboBoxProxy::IFWL_ComboBoxProxy(
     IFWL_ComboBox* pComboBox,
     const IFWL_App* app,
     std::unique_ptr<CFWL_WidgetProperties> properties,
     IFWL_Widget* pOuter)
     : IFWL_FormProxy(app, std::move(properties), pOuter),
@@ skipping 16 matching lines @@
           break;
         case FWL_MouseCommand::LeftButtonUp:
           OnLButtonUp(pMsg);
           break;
         default:
           break;
       }
       break;
     }
     case CFWL_MessageType::KillFocus:
-      OnFocusChanged(static_cast<CFWL_MsgKillFocus*>(pMessage), false);
+      OnFocusChanged(pMessage, false);
       break;
     case CFWL_MessageType::SetFocus:
-      OnFocusChanged(static_cast<CFWL_MsgKillFocus*>(pMessage), true);
+      OnFocusChanged(pMessage, true);
       break;
     default:
       break;
   }
   IFWL_Widget::OnProcessMessage(pMessage);
 }
 
 void IFWL_ComboBoxProxy::OnDrawWidget(CFX_Graphics* pGraphics,
                                       const CFX_Matrix* pMatrix) {
   m_pComboBox->DrawStretchHandler(pGraphics, pMatrix);
 }
 
-void IFWL_ComboBoxProxy::OnLButtonDown(CFWL_MsgMouse* pMsg) {
+void IFWL_ComboBoxProxy::OnLButtonDown(CFWL_Message* pMessage) {
   const IFWL_App* pApp = GetOwnerApp();
   if (!pApp)
     return;
 
   CFWL_NoteDriver* pDriver =
       static_cast<CFWL_NoteDriver*>(pApp->GetNoteDriver());
   CFX_RectF rtWidget;
   GetWidgetRect(rtWidget);
   rtWidget.left = rtWidget.top = 0;
+
+  CFWL_MsgMouse* pMsg = static_cast<CFWL_MsgMouse*>(pMessage);
   if (rtWidget.Contains(pMsg->m_fx, pMsg->m_fy)) {
     m_bLButtonDown = true;
     pDriver->SetGrab(this, true);
   } else {
     m_bLButtonDown = false;
     pDriver->SetGrab(this, false);
     m_pComboBox->ShowDropList(false);
   }
 }
 
-void IFWL_ComboBoxProxy::OnLButtonUp(CFWL_MsgMouse* pMsg) {
+void IFWL_ComboBoxProxy::OnLButtonUp(CFWL_Message* pMessage) {
   m_bLButtonDown = false;
   const IFWL_App* pApp = GetOwnerApp();
   if (!pApp)
     return;
 
   CFWL_NoteDriver* pDriver =
       static_cast<CFWL_NoteDriver*>(pApp->GetNoteDriver());
   pDriver->SetGrab(this, false);
   if (!m_bLButtonUpSelf) {
     m_bLButtonUpSelf = true;
     return;
   }
 
+  CFWL_MsgMouse* pMsg = static_cast<CFWL_MsgMouse*>(pMessage);
   CFX_RectF rect;
   GetWidgetRect(rect);
   rect.left = rect.top = 0;
   if (!rect.Contains(pMsg->m_fx, pMsg->m_fy) &&
       m_pComboBox->IsDropListVisible()) {
     m_pComboBox->ShowDropList(false);
   }
 }
 
-void IFWL_ComboBoxProxy::OnFocusChanged(CFWL_MsgKillFocus* pMsg, bool bSet) {
+void IFWL_ComboBoxProxy::OnFocusChanged(CFWL_Message* pMessage, bool bSet) {
   if (bSet)
     return;
+
+  CFWL_MsgKillFocus* pMsg = static_cast<CFWL_MsgKillFocus*>(pMessage);
   if (!pMsg->m_pSetFocus)
     m_pComboBox->ShowDropList(false);
 }