remotefilelog: acquire lock before writing requirements on clone Performing a shallow clone in remotefilelog does not acquire lock. This leads to following warning when we try to write some requirements in store: ``` --- /home/gps/src/hg-committed/tests/test-remotefilelog-share.t +++ /home/gps/src/hg-committed/tests/test-remotefilelog-share.t#safe.err @@ -28,6 +28,7 @@ $ hgcloneshallow ssh://user@dummy/master source --noupdate -q + devel-warn: write with no lock: "requires" at: /home/gps/src/hg-committed/mercurial/scmutil.py:1505 (writerequires) $ hg share source dest updating working directory 1 files updated, 0 files merged, 0 files removed, 0 files unresolved ``` Let's lock before writing the requirements file. Another solution which I can think of is not warn about missing lock when writing to requires file in store. Differential Revision: https://phab.mercurial-scm.org/D8952