Cleanup IFWL_Widget visibility and virtual parameters

xfa/fwl/core/ifwl_monthcalendar.h

Index: xfa/fwl/core/ifwl_monthcalendar.h
diff --git a/xfa/fwl/core/ifwl_monthcalendar.h b/xfa/fwl/core/ifwl_monthcalendar.h
index ec8cdcda8524b8c4e5008cec6272a01430048603..60679e27c80177cae3523f333709f3b5cdde86a6 100644
--- a/xfa/fwl/core/ifwl_monthcalendar.h
+++ b/xfa/fwl/core/ifwl_monthcalendar.h
@@ -57,10 +57,10 @@ class IFWL_MonthCalendar : public IFWL_Widget {
 
   // FWL_WidgetImp
   FWL_Type GetClassID() const override;
-  FWL_Error GetWidgetRect(CFX_RectF& rect, bool bAutoSize = false) override;
-  FWL_Error Update() override;
-  FWL_Error DrawWidget(CFX_Graphics* pGraphics,
-                       const CFX_Matrix* pMatrix = nullptr) override;
+  void GetWidgetRect(CFX_RectF& rect, bool bAutoSize = false) 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;