Klausw@, is this caused by your patch https://chromium-review.googlesource.com/c/chromium/src/+/1121344?

cc test owner just FYI

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/6263e2f576246b0a7ee226491f40cd5250449087

commit 6263e2f576246b0a7ee226491f40cd5250449087
Author: Yi Gu <yigu@chromium.org>
Date: Sat Jun 30 04:40:15 2018

Mark external/wpt/gyroscope/Gyroscope-iframe-access.https.html timeout on Mac10.12

TBR=klausw@chromium.org
NOTRY=True

Bug: 859270
Change-Id: I084037c5686e6ab7ac047556b64ff9dc49b41245
Reviewed-on: https://chromium-review.googlesource.com/1121676
Reviewed-by: Yi Gu <yigu@chromium.org>
Commit-Queue: Yi Gu <yigu@chromium.org>
Cr-Commit-Position: refs/heads/master@{#571761}
[modify] https://crrev.com/6263e2f576246b0a7ee226491f40cd5250449087/third_party/WebKit/LayoutTests/TestExpectations

yigu@, do you have a more specific link that points to my patch causing this? I was looking at the builder output, and the failures / crashes seemed to be related to a variety of tests that I wouldn't expect to be affected by this WebXR specific change.

Some examples via https://ci.chromium.org/p/chromium/builders/luci.chromium.ci/Mac10.12%20Tests

Unexpected Failures:
* plugins/embed-attributes-setting.html

Unexpected Failures:
* fast/canvas/color-space/canvas-colorManaged-convertToBlob-roundtrip.html

failures: [ long list of unrelated-looking tests ]

Unexpected Failures:
* __main__.ChromeDriverTest.testDoesntThrowWhenPageLogsUndefinedValue

Unexpected Failures:
* http/tests/devtools/runtime/evaluate-timeout.js
* http/tests/inspector-protocol/page/page-lifecycleEvents.js

crashpad_tests on Intel GPU on Mac on Mac-10.12.6 Run on OS: 'Mac-10.12.6'
Shard duration: 0:01:32.750989
failures:
HTTPTransport/HTTPTransport.ValidFormData_Gzip/0