Use enum class for subtypes of CPDF_Annot.

fpdfsdk/include/cpdfsdk_baannothandler.h

 // 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
 
 #ifndef FPDFSDK_INCLUDE_CPDFSDK_BAANNOTHANDLER_H_
 #define FPDFSDK_INCLUDE_CPDFSDK_BAANNOTHANDLER_H_
 
 #include "core/fxcrt/include/fx_basic.h"
@@ skipping 10 matching lines @@
 
 #ifdef PDF_ENABLE_XFA
 class CXFA_FFWidget;
 #endif  // PDF_ENABLE_XFA
 
 class CPDFSDK_BAAnnotHandler : public IPDFSDK_AnnotHandler {
  public:
   CPDFSDK_BAAnnotHandler();
   ~CPDFSDK_BAAnnotHandler() override;
 
-  CFX_ByteString GetType() override;
   FX_BOOL CanAnswer(CPDFSDK_Annot* pAnnot) override;
   CPDFSDK_Annot* NewAnnot(CPDF_Annot* pAnnot, CPDFSDK_PageView* pPage) override;
 #ifdef PDF_ENABLE_XFA
   CPDFSDK_Annot* NewAnnot(CXFA_FFWidget* hWidget,
                           CPDFSDK_PageView* pPage) override;
 #endif  // PDF_ENABLE_XFA
   void ReleaseAnnot(CPDFSDK_Annot* pAnnot) override;
   void DeleteAnnot(CPDFSDK_Annot* pAnnot) override;
   CFX_FloatRect GetViewBBox(CPDFSDK_PageView* pPageView,
                             CPDFSDK_Annot* pAnnot) override;
@@ skipping 63 matching lines @@
   void OnSelected(CPDFSDK_Annot* pAnnot) override;
   FX_BOOL OnSetFocus(CPDFSDK_Annot* pAnnot, uint32_t nFlag) override;
   FX_BOOL OnKillFocus(CPDFSDK_Annot* pAnnot, uint32_t nFlag) override;
 #ifdef PDF_ENABLE_XFA
   FX_BOOL OnXFAChangedFocus(CPDFSDK_Annot* pOldAnnot,
                             CPDFSDK_Annot* pNewAnnot) override;
 #endif  // PDF_ENABLE_XFA
 };
 
 #endif  // FPDFSDK_INCLUDE_CPDFSDK_BAANNOTHANDLER_H_