Allow callers to pass in the dirstate lock in most localrepo.py funcs. This makes it possible to take the lock once and commit a large number of patches, without having to read and write the dirstate for each patch.

adding a
adding b
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NONEXISTENT: No such file or directory
a
b
a: No such file or directory
NONEXISTENT: No such file or directory
b
a
NONEXISTENT: No such file in rev 9e1684505872
a
b