addTimedChild doesn't work with frame labels, only fame numbers

[stevenalanstark]

I haven't investigated thoroughly here, instead I just use a work around. But I still wanted to report the issue.

I would like this to work:

 targetClip.addTimedChild( mc, "label" );

but, instead, I need to:

let frameNum:number = targetClip._labelDict["label"];
targetClip.addTimedChild( mc, frameNum );

[bigtimebuddy]

Would welcoming a PR which supports the label or frame number. Looks like this would apply to addKeyframe, addTimedChild, addTimedMask and addTween. Seems like addAction already supports both.