layout: Add the ability to deactivate fullscreen surfaces

Deactivating fullscreen is a special case so we need to handle it
similarly to dialog/popups.

This adds an additional schedule for repaint in the fullscreen part to
force a redraw, otherwise deactivation/activation would need to inflict
any sort of damage to trigger a redraw.

Bug-AGL: SPEC-4348
Signed-off-by: Marius Vlad <marius.vlad@collabora.com>
Change-Id: I258543f43514af07dfed7b36531816e90561cc61