Cleanup forward declarations.

fpdfsdk/include/formfiller/FFL_FormFiller.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 FPDFSDK_INCLUDE_FORMFILLER_FFL_FORMFILLER_H_
 #define FPDFSDK_INCLUDE_FORMFILLER_FFL_FORMFILLER_H_
 
 #include "fpdfsdk/include/formfiller/FFL_CBA_Fontmap.h"
 #include "fpdfsdk/include/formfiller/FFL_IFormFiller.h"
 #include "fpdfsdk/include/fsdk_baseform.h"
 
 class CPDFDoc_Environment;
 class CPDFSDK_Annot;
-class CPDFSDK_Document;
 class CPDFSDK_PageView;
 class CPDFSDK_Widget;
 
 class CFFL_FormFiller : public IPWL_Provider, public CPWL_TimerHandler {
  public:
   CFFL_FormFiller(CPDFDoc_Environment* pApp, CPDFSDK_Annot* pAnnot);
   ~CFFL_FormFiller() override;
 
   virtual FX_RECT GetViewBBox(CPDFSDK_PageView* pPageView,
                               CPDFSDK_Annot* pAnnot);
@@ skipping 166 matching lines @@
                       CFX_RenderDevice* pDevice,
                       CFX_Matrix* pUser2Device,
                       FX_DWORD dwFlags) override;
 
  protected:
   FX_BOOL m_bMouseIn;
   FX_BOOL m_bMouseDown;
 };
 
 #endif  // FPDFSDK_INCLUDE_FORMFILLER_FFL_FORMFILLER_H_