Add WPTs that RTCStats.timestamp is expressed in "Performance time". - #48361
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For w3c/webrtc-pc#3005 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). [1] https://source.chromium.org/chromium/chromium/src/+/main:base/time/time.h;l=1180;drc=1a6106ec2fc932237359fe1f54334a66bc4886f1 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}
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For w3c/webrtc-pc#3005
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).
[1] https://source.chromium.org/chromium/chromium/src/+/main:base/time/time.h;l=1180;drc=1a6106ec2fc932237359fe1f54334a66bc4886f1
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}