Description

Updates the documentation on Element.reassemble to clarify that builds may get scheduled before it after a hot reload in the presence of animations, timers, or debuggers.

Several attempts were made to fix this issue; while the solution may be possible, it is unreasonably difficult and would probably break other things. The core problem is that even though the service isolate can try to push reassemble to the head of the queue, any async calls done at any point after that can interrupt some element getting a reassemble call. Pausing the animator fixes cases where animations cause this, but makes hot reload feel slow (animations stop for a fraction of a second or more) and doesn't solve the problem of other timers or async processes messing things up.

Related Issues

Clarifies #26503

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