WebAnimation Meta calls `.pause` after `.reverse`

[smhigley]

Bug

When trying to use controls: { reverse: true } with the WebAnimation meta, the internals will first call player.reverse() and then player.pause(), so it will never play in reverse.

It would probably be best to add an AnimationControls property of pause to handle pausing the animation separately.

[tomdye]

@smhigley for now does it work if you pass controls: { reverse: true, play: true } ?

It would perhaps be better to check for the existence of of the play property and compare it directly to false before calling pause rather than doing a basic truthy check as this is currently triggering a pause() when play is not present.

[smhigley]

@tomdye it does work with controls: { reverse: true, play: true }, although I think it's still worthwhile to have it match the Web Animation API unless there's a compelling reason to differ. I tried it out with:

if (play) {
	player.play();
} else if (play === false) {
	player.pause();
}

That works as I would expect. The one snag is that it causes animations to play by default, which might create some unexpected behavior to anyone already using the WebAnimation meta. I think that's a good change in the long run, as it would match the default behavior of the Web Animation API. How would you feel about changing this with the breaking move to @dojo/framework?