
PASS Idle -> Active 
PASS Idle -> After 
PASS Before -> Active 
PASS Before -> After 
PASS Active -> Idle, display: none 
PASS Active -> Idle, setting Animation.timeline = null 
PASS Active -> Idle, calling Animation.cancel() 
PASS Active -> Before 
PASS Active -> After 
PASS After -> Before 
PASS After -> Active 
PASS Active -> Active (forwards) 
PASS Active -> Active (backwards) 
PASS Active -> Idle -> Active: animationstart is fired by restarting animation 
PASS Negative playbackRate sanity test(Before -> Active -> Before) 
PASS Redundant change, before -> active, then back 
PASS Redundant change, before -> after, then back 
PASS Redundant change, active -> before, then back 
PASS Redundant change, active -> after, then back 
PASS Redundant change, after -> before, then back 
PASS Redundant change, after -> active, then back 
PASS Call Animation.cancel after canceling animation. 
PASS Restart animation after canceling animation immediately. 
PASS Call Animation.cancel after restarting animation immediately. 
PASS Set timeline and play transition after clearing the timeline. 
PASS Set null target effect after canceling the animation. 
PASS Cancel the animation after clearing the target effect.