Remove xfa_common.h and IWYU.

xfa/src/fxfa/src/app/xfa_ffchoicelist.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/src/foxitlib.h"
 #include "xfa/src/fxfa/src/app/xfa_ffchoicelist.h"
 #include "xfa/src/fxfa/src/app/xfa_ffdoc.h"
 #include "xfa/src/fxfa/src/app/xfa_ffdocview.h"
 #include "xfa/src/fxfa/src/app/xfa_fffield.h"
 #include "xfa/src/fxfa/src/app/xfa_ffpageview.h"
 #include "xfa/src/fxfa/src/app/xfa_ffwidget.h"
 #include "xfa/src/fxfa/src/app/xfa_fwladapter.h"
-#include "xfa/src/fxfa/src/common/xfa_common.h"
+
 CXFA_FFListBox::CXFA_FFListBox(CXFA_FFPageView* pPageView,
                                CXFA_WidgetAcc* pDataAcc)
     : CXFA_FFField(pPageView, pDataAcc), m_pOldDelegate(NULL) {}
 CXFA_FFListBox::~CXFA_FFListBox() {
   if (m_pNormalWidget) {
     IFWL_Widget* pWidget = m_pNormalWidget->GetWidget();
     IFWL_NoteDriver* pNoteDriver = FWL_GetApp()->GetNoteDriver();
     pNoteDriver->UnregisterEventTarget(pWidget);
   }
 }
@@ skipping 503 matching lines @@
       break;
     }
     default: {}
   }
   return m_pOldDelegate->OnProcessEvent(pEvent);
 }
 FWL_ERR CXFA_FFComboBox::OnDrawWidget(CFX_Graphics* pGraphics,
                                       const CFX_Matrix* pMatrix) {
   return m_pOldDelegate->OnDrawWidget(pGraphics, pMatrix);
 }