Add dialog for testing motion detection.

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I'd like to clean this up after we have testing in. I don't like it.

Given a timeout time of _t_ ms, if I postDelayed for _t_ ms, the timeout check happens before _t_ ms (because postDelayed is an approximate delay). The timeout check has a confirmation that _t_ ms has passed (I can't recall why I confirm this, need to ponder more), if not, check again in _t_ ms. If there is no addedDelay, the timeout check has to run twice instead of once to check. This was annoying for debugging, the only negative effect is that the timeout check has to run a second time to see that _t_ has passed.