GUI some icon of QT 5.12.0 are not smooth

After adding a red line in ColorOverlay.qml which is 5.12.0 version QT framework code will cause this issue.  

  SourceProxy {
        id: sourceProxy
        input: rootItem.source  

       interpolation: rootItem.smooth || (rootItem.layer.enabled && rootItem.layer.smooth) ? SourceProxy.NearestInterpolation :  SourceProxy.LinearInterpolation

    }

--------------------Fail case-----------------------------------

-----------------Pass case---------------------------