Failed here: https://build.chromium.org/p/chromium.webkit/builders/WebKit%20Win7/builds/57253

Nothing in the revision range looks relevant and it passed on the following run. Failure range is 514135-514140. I also looked further back and didn't see anything particularly relevant.

Here's the ouptput:
09:30:42.932 5708 worker/1 virtual/mojo-loading/http/tests/media/autoplay-crossorigin.html output stderr lines:
09:30:42.932 5708   [3176:3192:1106/093042.877:ERROR:audio_manager_base.cc(316)] Invalid audio output parameters received; using fake audio path. Channels: 0, Sample Rate: 0, Bits Per Sample: 0, Frames Per Buffer: 0
09:30:42.952 7012 [55/57] virtual/mojo-loading/http/tests/media/autoplay-crossorigin.html failed unexpectedly (text diff)
09:30:42.952 5708 worker/1 virtual/mojo-loading/http/tests/media/autoplay-crossorigin.html failed:
09:30:42.952 5708 worker/1  text diff