test timeout observation

While looking for examples of timeouts not being reported as failures, the
persistent session tests for Clear Key stood out. Only one of the six shows
a result in the "all" page.

http://www.w3c-test.org/encrypted-media/clearkey-mp4-playback-persistent-license.html
times out in all three browsers, and when I run it, it is just blank for a
long time until I see:

> Harness status: Error
> Uncaught ReferenceError: qualifier is not defined


http://www.w3c-test.org/encrypted-media/clearkey-mp4-playback-persistent-usage-record.html,
in contrast, times out immediately

> Harness status: OK
> ...
>
Timeout org.w3.clearkey, successful playback, persistent-usage-record, mp4,
> set src before setMediaKeys

NotSupportedError: None of the requested configurations were supported.


Observations:

   - Harness ERROR is reported as a timeout.
   - A timeout in the test is not reported.
   - It's strange that the second test times out immediately even though it
   fails as we would expect.
   - These two playback should in theory be very similar but fail
   differently. Maybe that is because the first loads the session before
   playback (I assume).