Fix upstream merge conflict on 621fecfe5cd6
Merging upstream commit 621fecfe5cd6 gives a conflict.
A human being has to perform merge and resolution for the automatic merge process to resume.
Command for clean conflict reproduction:
hg pull
hg --config command.update.check=abort update 27a1071748745b4291f8849fed5d56d2417164a0 && \
hg topic upstream-merge && \
hg merge 621fecfe5cd67e187a1b4b4717e3d58962c0d91f