Adam Barth 25ab5555b7 Elide fewer AnimationStatus callbacks
Previously we would elide forward and reverse callbacks that canceled each
other out, which broke the expected state machine. Now we synchronously deliver
status callbacks when start an animation.

Fixes #1913
2016-02-26 16:29:14 -08:00
..
2016-02-12 17:26:52 -08:00