Gallery2: reduce the latency between cam&camcorder switch

There are animations of fadeIn and fadeOut effect when switching
from camera to camcorder or vice-versa which all last 300ms, thus
the black UI observed too long. Set the animator duration to a tiny
value for reducing this latency.

Change-Id: I9cee228e641ad82e7001e091944a30515f96ab2e
1 file changed