Disable ActionBar animations pending more involved fix

Recycling of ActionBar items can cause problems with the current
ActionBar animations, as the system animates views that represent both
pre- and post-layout changes, sometimes causing opposit animations to
run on the same view, resulting in unpredictable effect slike views
remaining invisible.

This 'fix' is a workaround to disable item animations pending a more
complete and robust fix that involves a more involved system of view
recycling that would avoid recycling views that are currently being used
in animations.

Issue #20538912 Menu missing in Downloads app

Change-Id: I7b1d3baf94378e4788f868801a452c6583353842