Cleanup IFWL_Widget visibility and virtual parameters

xfa/fwl/core/ifwl_spinbutton.h

Index: xfa/fwl/core/ifwl_spinbutton.h
diff --git a/xfa/fwl/core/ifwl_spinbutton.h b/xfa/fwl/core/ifwl_spinbutton.h
index 73c2fc063935d6d848431fc9675af4a16e025193..f2d3c0203a9bfa47bdc328648c8f4233a61f420c 100644
--- a/xfa/fwl/core/ifwl_spinbutton.h
+++ b/xfa/fwl/core/ifwl_spinbutton.h
@@ -27,11 +27,11 @@ class IFWL_SpinButton : public IFWL_Widget {
 
   // IFWL_Widget
   FWL_Type GetClassID() const override;
-  FWL_Error GetWidgetRect(CFX_RectF& rect, bool bAutoSize = false) override;
-  FWL_Error Update() override;
+  void GetWidgetRect(CFX_RectF& rect, bool bAutoSize = false) override;
+  void Update() override;
   FWL_WidgetHit HitTest(FX_FLOAT fx, FX_FLOAT fy) override;
-  FWL_Error DrawWidget(CFX_Graphics* pGraphics,
-                       const CFX_Matrix* pMatrix = nullptr) override;
+  void DrawWidget(CFX_Graphics* pGraphics,
+                  const CFX_Matrix* pMatrix = nullptr) override;
   void OnProcessMessage(CFWL_Message* pMessage) override;
   void OnProcessEvent(CFWL_Event* pEvent) override;
   void OnDrawWidget(CFX_Graphics* pGraphics,