Fix flash due to not freezing screen when start/end resizing

Instead of freezing the entire screen, preserve the window's old
surface and put it on a layer that's above other windows (while
still below the screen rotation freeze layer). Only remove the
surface when animation starts after the new drawing is received.

bug: 24715185

Change-Id: I1d2b873d339d672cea0f18679b5622cea69bd449