Make more CPDF_Parser method const.

fpdfsdk/include/fsdk_annothandler.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_FSDK_ANNOTHANDLER_H_
 #define FPDFSDK_INCLUDE_FSDK_ANNOTHANDLER_H_
 
 #include <map>
 #include <vector>
 
 #include "core/include/fxcrt/fx_basic.h"
 
 class CFFL_IFormFiller;
 class CFX_RenderDevice;
 class CPDFDoc_Environment;
 class CPDFSDK_Annot;
 class CPDFSDK_PageView;
 class CPDF_Annot;
 class CFX_Matrix;
 class CPDF_Point;
-class CPDF_Rect;
 
 class IPDFSDK_AnnotHandler {
  public:
   virtual ~IPDFSDK_AnnotHandler() {}
 
   virtual CFX_ByteString GetType() = 0;
 
   virtual CFX_ByteString GetName() = 0;
 
   virtual FX_BOOL CanAnswer(CPDFSDK_Annot* pAnnot) = 0;
@@ skipping 280 matching lines @@
  private:
   CPDFSDK_Annot* NextAnnot();
   CPDFSDK_Annot* PrevAnnot();
 
   std::vector<CPDFSDK_Annot*> m_iteratorAnnotList;
   const bool m_bReverse;
   size_t m_pos;
 };
 
 #endif  // FPDFSDK_INCLUDE_FSDK_ANNOTHANDLER_H_