Avoid blitting at negative yValue offset
Avoid blitting at negative yValue offset

timfel/squeakvm,timfel/squeakvm,timfel/squeakvm,timfel/squeakvm,timfel/squeakvm,OpenSmalltalk/vm,timfel/squeakvm,OpenSmalltalk/vm,timfel/squeakvm,OpenSmalltalk/vm,timfel/squeakvm,OpenSmalltalk/vm,OpenSmalltalk/vm,OpenSmalltalk/vm,OpenSmalltalk/vm,OpenSmalltalk/vm