base

Ensure we update window scale when repositioning child.

In repositionChild we need to ensure we update the window scale
if the layout dimensions change without changing the surface size.
If we are doing such it seems to make more sense to update
the layout params than the window frame.

Bug: 25791641
Change-Id: I24ab0011936acb45e6cdf60af52edc8d9419d91e