Tiling: Fix some issues and simplify code.
Tiling: Fix some issues and simplify code.

This fixes the issue with a floating window turned tiled and then closed
leaving a ghost window.

tizenorg/platform.upstream.enlightenment,FlorentRevest/Enlightenment,tizenorg/platform.upstream.enlightenment,rvandegrift/e,tasn/enlightenment,tasn/enlightenment,tasn/enlightenment,FlorentRevest/Enlightenment,rvandegrift/e,tizenorg/platform.upstream.enlightenment,FlorentRevest/Enlightenment,rvandegrift/e