GridView - Negative ContentY

Changing the cellWidth and cellHeight in Gridview

while being at a contentY greater than 0 will mess up the contentY - if you return to what should be contentY 0 you will be at negative contentY

to fix contentY you can call 

positionViewAtBeginning

note that

positionViewAtIndex(0, GridView.visible) did not work to make contentY a positive (or 0) number again

forceLayout() did not help as well

returnToBounds() also did not