Fix upstream merge conflict on 8f379387ad34
Merging upstream commit 8f379387ad34 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 heptapod && \
hg topic upstream-merge && \
hg merge 8f379387ad340546222bdcaf7f949042575435a0