drawdag: don't crash when writing copy info to changesets
When writing copies to the changeset, localrepo.commitctx() will call
ctx.p1copies() and ctx.p2copies(). These crashed on simplecommitctx
because they ended up trying to access the manifest. drawdag doesn't
support copies at all, so we can simply override the methods to return
empty dicts.
Differential Revision: https://phab.mercurial-scm.org/D6565
#require test-repo jshint hg10
$ . "$TESTDIR/helpers-testrepo.sh"
run jshint on all tracked files ending in .js except vendored dependencies
$ cd "`dirname "$TESTDIR"`"
$ testrepohg locate 'set:**.js' \
> 2>/dev/null \
> | xargs jshint