Reversing immediately after starting animator ends it

Previously, an animator that had started but not yet played its
first frame would be reversed from its end state, which was not the
desired behavior. Now, we detect that condition (started, but not yet
actually running) and simply end() the animator immediately.

Issue #10136266 ValueAnimator.reverse right after calling start() does the full animation

Change-Id: I2a48d267336241ce74079c75758026c6f07ebc3a