Fix CFWL_WidgetImpDelegate hierarchy.

xfa/src/fwl/src/basewidget/include/fwl_pushbuttonimp.h

Index: xfa/src/fwl/src/basewidget/include/fwl_pushbuttonimp.h
diff --git a/xfa/src/fwl/src/basewidget/include/fwl_pushbuttonimp.h b/xfa/src/fwl/src/basewidget/include/fwl_pushbuttonimp.h
index b346e52f12124bdc3f5d62c221db839aafae5bca..29856298544d3d4670642ac72ff8ff740c1ffe89 100644
--- a/xfa/src/fwl/src/basewidget/include/fwl_pushbuttonimp.h
+++ b/xfa/src/fwl/src/basewidget/include/fwl_pushbuttonimp.h
@@ -47,10 +47,10 @@ class CFWL_PushButtonImp : public CFWL_WidgetImp {
 class CFWL_PushButtonImpDelegate : public CFWL_WidgetImpDelegate {
  public:
   CFWL_PushButtonImpDelegate(CFWL_PushButtonImp* pOwner);
-  virtual int32_t OnProcessMessage(CFWL_Message* pMessage);
-  virtual FWL_ERR OnProcessEvent(CFWL_Event* pEvent);
-  virtual FWL_ERR OnDrawWidget(CFX_Graphics* pGraphics,
-                               const CFX_Matrix* pMatrix = NULL);
+  int32_t OnProcessMessage(CFWL_Message* pMessage) override;
+  FWL_ERR OnProcessEvent(CFWL_Event* pEvent) override;
+  FWL_ERR OnDrawWidget(CFX_Graphics* pGraphics,
+                       const CFX_Matrix* pMatrix = NULL) override;
 
  protected:
   void OnFocusChanged(CFWL_Message* pMsg, FX_BOOL bSet = TRUE);