Remove include only fwl.h and IWYU.

xfa/src/fxfa/src/app/xfa_ffapp.h

 // 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
 
 #ifndef XFA_SRC_FXFA_SRC_APP_XFA_FFAPP_H_
 #define XFA_SRC_FXFA_SRC_APP_XFA_FFAPP_H_
 
+#include "core/include/fpdfapi/fpdf_objects.h"
+#include "xfa/include/fwl/adapter/fwl_adapternative.h"
+#include "xfa/include/fwl/adapter/fwl_sdadapterimp.h"
+#include "xfa/include/fwl/core/fwl_app.h"
+#include "xfa/include/fxfa/fxfa.h"
+#include "xfa/src/fgas/include/fx_fnt.h"
+
+class CXFA_FWLAdapterWidgetMgr;
+class CXFA_FWLTheme;
+class CXFA_FFDocHandler;
+class CXFA_FFMenuHandler;
+class CXFA_FontMgr;
+
 class CXFA_FileRead : public IFX_FileRead {
  public:
   explicit CXFA_FileRead(const CFX_ArrayTemplate<CPDF_Stream*>& streams);
 
   virtual FX_FILESIZE GetSize();
   virtual FX_BOOL ReadBlock(void* buffer, FX_FILESIZE offset, size_t size);
 
   virtual void Release() { delete this; }
 
  protected:
   CFX_ObjectArray<CPDF_StreamAcc> m_Data;
 };
-class CXFA_FWLAdapterWidgetMgr;
-class CXFA_FWLTheme;
-class CXFA_FFDocHandler;
-class CXFA_FFMenuHandler;
-class CXFA_FontMgr;
+
 class CXFA_FFApp : public IXFA_App, public IFWL_AdapterNative {
  public:
   CXFA_FFApp(IXFA_AppProvider* pProvider);
   ~CXFA_FFApp() override;
 
   // IFXFA_App:
   IXFA_DocHandler* GetDocHandler() override;
   IXFA_Doc* CreateDoc(IXFA_DocProvider* pProvider,
                       IFX_FileRead* pStream,
                       FX_BOOL bTakeOverFile) override;
@@ skipping 26 matching lines @@
   IFX_FontSourceEnum* m_pFontSource;
 #endif
   CXFA_FWLAdapterWidgetMgr* m_pAdapterWidgetMgr;
   IFWL_WidgetMgrDelegate* m_pWidgetMgrDelegate;
   IFX_FontMgr* m_pFDEFontMgr;
   CXFA_FFMenuHandler* m_pMenuHandler;
   CFWL_SDAdapterThreadMgr* m_pAdapterThreadMgr;
 };
 
 #endif  // XFA_SRC_FXFA_SRC_APP_XFA_FFAPP_H_