Change bool type to fix warnings.

fpdfsdk/cfx_systemhandler.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_CFX_SYSTEMHANDLER_H_
 #define FPDFSDK_CFX_SYSTEMHANDLER_H_
 
 #include "core/fxcrt/include/fx_coordinates.h"
@@ skipping 47 matching lines @@
   bool IsSelectionImplemented() const;
 
   void SetCursor(int32_t nCursorType);
 
   bool FindNativeTrueTypeFont(int32_t nCharset, CFX_ByteString sFontFaceName);
   CPDF_Font* AddNativeTrueTypeFontToPDF(CPDF_Document* pDoc,
                                         CFX_ByteString sFontFaceName,
                                         uint8_t nCharset);
   int32_t SetTimer(int32_t uElapse, TimerCallback lpTimerFunc);
   void KillTimer(int32_t nID);
-  bool IsSHIFTKeyDown(uint32_t nFlag) const;
-  bool IsCTRLKeyDown(uint32_t nFlag) const;
-  bool IsALTKeyDown(uint32_t nFlag) const;
-  bool IsINSERTKeyDown(uint32_t nFlag) const;
+  FX_BOOL IsSHIFTKeyDown(uint32_t nFlag) const;
+  FX_BOOL IsCTRLKeyDown(uint32_t nFlag) const;
+  FX_BOOL IsALTKeyDown(uint32_t nFlag) const;
 
   FX_SYSTEMTIME GetLocalTime();
 
   int32_t GetCharSet() const { return m_nCharSet; }
   void SetCharSet(int32_t nCharSet) { m_nCharSet = nCharSet; }
 
  private:
   CPDFDoc_Environment* const m_pEnv;
   int m_nCharSet;
 };
 
 #endif  // FPDFSDK_CFX_SYSTEMHANDLER_H_