Remove oGPUUtil for readbacks.
Remove oGPUUtil for readbacks.
jiangzhu1212/oooii,jiangzhu1212/oooii,jiangzhu1212/oooii,jiangzhu1212/oooii,jiangzhu1212/oooii,jiangzhu1212/oooii,jiangzhu1212/oooii,jiangzhu1212/oooii,jiangzhu1212/oooii