We currently start the timeout as soon as the player enters
the target ad, but that ad hasn't loaded yet (= at the point
where we actively start waiting for it). And then we try to
clear the timeout at various places that mean we are no longer
waiting for this ad. This is very error-prone though because
there are a lot of places in the AdTagLoader that change the
AdPlaybackState and could mark the ad as skipped, failed or
loaded.
A much less error-prone way of clearing the timeout is not
even try to find all places that may revert the wait condition
and instead just check if we are still waiting at the point
of executing the timeout message.
PiperOrigin-RevId: 748291720
5d540acbeb