Flaking tests due to upstream Chromium bug (`Check failed: ThreadCache::IsValid`)

[kaylendog]

There's an upstream issue in chromium that is crashing chrome while running complement-crypto that causes flaking on seemingly arbitrary tests.

Runs:

• https://github.com/matrix-org/matrix-js-sdk/actions/runs/23551202028/job/68565387173
• https://github.com/matrix-org/matrix-js-sdk/actions/runs/23551894326/job/68567881911

Upstream issue: https://issues.chromium.org/issues/483092892

[andybalaam]

We think apt-updating chromium in complement-crypto's CI will fix this.

[richvdh]

The errors are of the form:

      lang_jssdk.go:42: must.NotError: NewJSClient: %s -> failed to RunHeadless: failed to run test evaluation via chromedp: chrome failed to start:
          [FATAL:scheduler_loop_quarantine_support.h(101)] Check failed: ThreadCache::IsValid(tcache). 
          #00 0x55c1b0ee2222  (/usr/local/share/chromium/chrome-linux/chrome+0xa75a222)
          #01 0x55c1b0e34990  (/usr/local/share/chromium/chrome-linux/chrome+0xa6ac990)
          #02 0x55c1b0e3398f  (/usr/local/share/chromium/chrome-linux/chrome+0xa6ab98f)
          #03 0x55c1b0e33791  (/usr/local/share/chromium/chrome-linux/chrome+0xa6ab791)
          #04 0x55c1b0e523ca  (/usr/local/share/chromium/chrome-linux/chrome+0xa6ca3ca)
          #05 0x55c1b0e51e8b  (/usr/local/share/chromium/chrome-linux/chrome+0xa6c9e8b)
          #06 0x55c1b0eb9fc8  (/usr/local/share/chromium/chrome-linux/chrome+0xa731fc8)
          #07 0x55c1b0e52bda  (/usr/local/share/chromium/chrome-linux/chrome+0xa6cabda)
          #08 0x55c1b0e10831  (/usr/local/share/chromium/chrome-linux/chrome+0xa688831)
          #09 0x55c1b0e75ca8  (/usr/local/share/chromium/chrome-linux/chrome+0xa6edca8)
          #10 0x55c1b0e60bcd  (/usr/local/share/chromium/chrome-linux/chrome+0xa6d8bcd)
          #11 0x55c1b0e75e4a  (/usr/local/share/chromium/chrome-linux/chrome+0xa6ede4a)
          #12 0x55c1b0e8d8fa  (/usr/local/share/chromium/chrome-linux/chrome+0xa7058fa)
          [21893:21910:0325/161501.279122:ERROR:dbus/bus.cc:405] Failed to connect to the bus: Could not parse server address: Unknown address type (examples of valid types are "tcp" and on UNIX "unix")
          #13 0x7efcf6e94ac3  (/usr/lib/x86_64-linux-gnu/libc.so.6+0x94ac3)
          [0325/161501.390824:ERROR:third_party/crashpad/crashpad/util/file/file_io_posix.cc:145] open /sys/devices/system/cpu/cpu0/cpufreq/scaling_cur_freq: No such file or directory (2)
          [0325/161501.474576:ERROR:third_party/crashpad/crashpad/util/file/file_io_posix.cc:145] open /sys/devices/system/cpu/cpu0/cpufreq/scaling_max_freq: No such file or directory (2)

(everything after 'failed to start' is the combined stderr and stdout of the chrome process, until it exits)

As Skye says, this looks to be https://issues.chromium.org/issues/483092892. That was introduced in https://chromium-review.googlesource.com/c/chromium/src/+/7519605 (Chromium 146.0.7679.0) and then reduced the next day in https://chromium-review.googlesource.com/c/chromium/src/+/7562909 (147.0.7681.0). Of course, the Github Ubuntu 22.04 runner has 146.0.7680.0; that rolled out on 20260322.

The revert was later itself reverted in https://chromium-review.googlesource.com/c/chromium/src/+/7580337 (147.0.7714.0), thanks to a fix of the underlying logic.

In any case, upgrading Chromium should fix this, though presumably that only needs to be a temporary step until Github updates their Ubuntu runners again.