Fix "incall in landscape sometimes" bug #2523942

The problem turns out to have been a deep weirdness in the way that keyguard
and incall interact.  Incall gets relaunched when the keyboard is opened/closed,
which transiently exposes keyguard with its nosensor orientation demands, and
that plus the long keyguard-hide animation was leaving incall in a bad state
from which the window manager didn't try to recover.

We now disregard animating-towards-hidden windows [i.e. keyguard] when running
through the app tokens to determine what orientation should be, and do not do
configuration calculations at all while the display is frozen.  There can still
be a transient state in which incall is drawn in landscape, but things proceed
from there to relaunch it back into the proper portrait orientation, and it
ends up in the right state in the end.

Change-Id: I0d74ee19064b6d7f65600976f1b5b16b7ec36f31