obj.clearRowModel() results in missing rows-Not fixed in AW 2.6.4

Which is due to the height getting setted in the id myGrid-scroll-box-spacer

This issue can be fixed by setting after clearRowModel(),
rowHeight = obj.getContent("box/sample").element().offsetHeight;
obj.setRowHeight(rowHeight);
or
obj.setRowHeight(20);

This fix can not support the latest version of AW 2.6.4.

Could you please help out of it