Fix bug in LayoutTransition for INVISIBLE views

When a view is becoming VISIBLE or INVISIBLE in a container with a
LayoutTransition, animations run to fade the view in and out and also
to run 'changing' animations on the view's other siblings. This logic
also cancels any running 'changin' animations to account for new ones
running.

However, in the specific case of INVISIBLE changes, there will be no
layout changes in the container - layout has already accounted for that
view (unlike in the case of GONE views); the visibility is just a matter of
drawing the view (or not). Therefore, we're canceling 'changing' animations
that should continue running and not replacing them with any other animations,
since new animations would only be started on layout chnages which are not
forthcoming.

One artifact seen from this bug is that the navigation bar buttons sometimes
disappear when changing orientation. This is because the menu button may
toggle between VISIBLE and INVISIBLE, causing animations on the other
buttons to get canceled, which leaves those views in a completely wrong
state.

The right thing to do is to avoid canceling in-process 'changing' animations
and to skip the logic of setting up new 'changing' animations which won't fire
anyway.

There is some minor API work in here because we did not previously have the
necessary information in LayoutTransition to know whether a view was being
hidden or shown to/from the INVISIBLE state.

Issue #5911213: LayoutTransitions ending in an odd state

Change-Id: I5c60c8583c8ea08965727b4ef17b550c40a3882c