Cleanup IFWL_Widget visibility and virtual parameters

xfa/fwl/core/ifwl_pushbutton.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_IFWL_PUSHBUTTON_H_
 #define XFA_FWL_CORE_IFWL_PUSHBUTTON_H_
 
 #include "xfa/fwl/core/cfwl_widgetproperties.h"
@@ skipping 26 matching lines @@
 };
 
 class IFWL_PushButton : public IFWL_Widget {
  public:
   IFWL_PushButton(const IFWL_App* app,
                   std::unique_ptr<CFWL_WidgetProperties> properties);
   ~IFWL_PushButton() override;
 
   // IFWL_Widget
   FWL_Type GetClassID() const override;
-  FWL_Error GetWidgetRect(CFX_RectF& rect, bool bAutoSize = false) override;
+  void GetWidgetRect(CFX_RectF& rect, bool bAutoSize = false) override;
   void SetStates(uint32_t dwStates, bool bSet = true) override;
-  FWL_Error Update() override;
-  FWL_Error DrawWidget(CFX_Graphics* pGraphics,
-                       const CFX_Matrix* pMatrix = nullptr) override;
+  void Update() 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;
 
  protected:
   void DrawBkground(CFX_Graphics* pGraphics,
                     IFWL_ThemeProvider* pTheme,
                     const CFX_Matrix* pMatrix);
   void DrawText(CFX_Graphics* pGraphics,
                 IFWL_ThemeProvider* pTheme,
@@ skipping 10 matching lines @@
  private:
   void OnFocusChanged(CFWL_Message* pMsg, bool bSet);
   void OnLButtonDown(CFWL_MsgMouse* pMsg);
   void OnLButtonUp(CFWL_MsgMouse* pMsg);
   void OnMouseMove(CFWL_MsgMouse* pMsg);
   void OnMouseLeave(CFWL_MsgMouse* pMsg);
   void OnKeyDown(CFWL_MsgKey* pMsg);
 };
 
 #endif  // XFA_FWL_CORE_IFWL_PUSHBUTTON_H_