imported/w3c/web-platform-tests/media-source/mediasource-sourcebuffer-mode.html has started crashing somewhere between r221918 and r221929. The had consistently no errors before that.
Marked as expected crash in r221992. Please update expectations when fixed.
I can't repro this but bots seem to catch some rare flakyness on crash and text.
This test has been already unskipped and is now passing both locally for me and in the Webkit Results Database[1] since (at least) r236743. I'm closing this bug. [1] https://results.webkit.org/?suite=layout-tests&test=imported%2Fw3c%2Fweb-platform-tests%2Fmedia-source%2Fmediasource-sourcebuffer-mode.html