Remove windowmanager hacks form the incubation controller.

Remove windowmanager hacks form the incubation controller.

Tie incubation directly to wether animations are running
or not. When animations are running, we incubate for
a third of a frame only. When animations are not running
we incubate whatever is left as the scene is anyway idle.

Change-Id: I88c9248e9d7b3b35c99fca52aeb9c681d1b4a306
Reviewed-by: Martin Jones <martin.jones@nokia.com>