There are no obvious culprits in the chrome change log, but several potential ones.

I am going to see if I can reproduce this locally, although I haven't built tricky before so it will take a while.

This is no longer happening.
FWIW, I was able to reproduce it locally but it is fixed in ToT.
Presumably this was a bug that affected other builders and was identified and fixed or reverted.
There were two build failures after the last failure with this symptom, so there is a long range of possible changes that may have caused this.

I may try to do a bisect anyway if I have time just to know what caused this.

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Pri-0 bugs are critical regressions or serious emergencies, and this bug has not been updated in three days. Could you please provide an update, or adjust the priority to a more appropriate level if applicable?

If a fix is in active development, please set the status to Started.

Thanks for your time! To disable nags, add the Disable-Nags label.

For more details visit https://www.chromium.org/issue-tracking/autotriage - Your friendly Sheriffbot