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

merge with stable

bookmarks: actual fix for race condition deleting bookmark This is a simple but efficient fix to prevent the issue tested in `test-bookmarks-corner-case.t`. It might be worth pursuing a more generic approach where filecache learn to depend on each other, but that would not be suitable for stable. The issue is complicated enough that I documented the race and its current solution as inline comment. See this comment for details on the fix.