Fix problem with BootAnimation exit
After the completion of each animation part, the boot animation must
sleep for the number of frames specified in part.pause. If this is
done in a single sleep statement, it is possible that the boot animation
will continue to display long after surface flinger has finished booting.

To address that, the pause between parts is done in a loop and on each
iteration, the property that surface flinger sets to indicate that animation
should exit is checked.  This minimizes, but doesn't remove, the likelihood
that the bootanimation is visible when the UI comes up.

Change-Id: I6e2c9fb7a7fc8f3f63c13a8b85cabec043e5dc36
Merge "Fix problem with BootAnimation exit After the completion of each animation part, the boot animation must sleep for the number of frames specified in part.pause. If this is done in a single sleep statement, it is possible that the boot animation will continue to display long after surface flinger has finished booting." into pac-4.4