Add WPTs that RTCStats.timestamp is expressed in "Performance time".
Sadly Date.now() and performance.timeOrigin + performance.now() only
diverge in edge cases (e.g. laptop going to sleep or wall clock
changing while web page is still open?) so these WPTs may give false
positives to Wall Clock implementations, but they will at least
fail if clock is completely off and document correct behavior.
The current implementation is wrong, but we still pass the test because
of no divergence here. We need to exclude Windows at the moment though
because some of its clocks has precision limitations (example: [1]) and
there seems to be some mismatch between WebRTC's current clock impl and
Performance that becomes visible in this WPT (just a few ms delta).
Bug: chromium:369369568
Change-Id: Iad452519800aa4c41427317d29e4fb11235b2f37
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/5887191
Commit-Queue: Henrik Boström hbos@chromium.org
Reviewed-by: Harald Alvestrand hta@chromium.org
Cr-Commit-Position: refs/heads/main@{#1361140}