Cleanup caret show/hide code

xfa/fwl/core/cfwl_caret.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_FWL_CORE_CFWL_CARET_H_
 #define XFA_FWL_CORE_CFWL_CARET_H_
 
 #include <memory>
@@ skipping 16 matching lines @@
 
   // CFWL_Widget
   FWL_Type GetClassID() const override;
   void DrawWidget(CFX_Graphics* pGraphics,
                   const CFX_Matrix* pMatrix = nullptr) override;
   void OnProcessMessage(CFWL_Message* pMessage) override;
   void OnDrawWidget(CFX_Graphics* pGraphics,
                     const CFX_Matrix* pMatrix) override;
   void Update() override;
 
-  void ShowCaret(bool bFlag = true);
+  void ShowCaret();
+  void HideCaret();
 
  private:
   class Timer : public CFWL_Timer {
    public:
     explicit Timer(CFWL_Caret* pCaret);
     ~Timer() override {}
 
     void Run(CFWL_TimerInfo* hTimer) override;
   };
   friend class CFWL_Caret::Timer;
 
   void DrawCaretBK(CFX_Graphics* pGraphics,
                    IFWL_ThemeProvider* pTheme,
                    const CFX_Matrix* pMatrix);
 
   std::unique_ptr<CFWL_Caret::Timer> m_pTimer;
   CFWL_TimerInfo* m_pTimerInfo;  // not owned.
 };
 
 #endif  // XFA_FWL_CORE_CFWL_CARET_H_