branching: merge stable into default

Added signature for changeset 8830004967ad

Added tag 6.3.3 for changeset 8830004967ad

relnotes: add 6.3.3

typing: add typehints to mercurial/diffutil.py Lack of typehints here caused the fact that TortoiseHg was passing str instead of bytes as the key in `opts` to be missed, resulting in shelf corruption in cases where `diff.git` is required.

patchbomb: respect the `--git` option I *think* this is the only diffopt exposed on the command line. TortoiseHg had a similar issue creating diffopts, and this was caught by type hints in the next commit.

rhg: remember the inode of .hg/dirstate This allows us to detect changes of `.hg/dirstate`, which is either the full dirstate (in dirstate-v1) or the docket file (v2) without relying on data inside the file. It only works on UNIX systems. This fixes a race condition for dirstate-v1 (as demonstrated by the test changes) and adds a confortable layer of sanity for dirstate-v2.

rust-dirstate-v2: don't write dirstate if data file has changed This fixes the following race: - process A reads the dirstate - process B reads and writes the dirstate - process A writes the dirstate This either resulted in losing what process B had just written or a crash because the `uuid` had changed and we were trying to write to a file that doesn't exist. More explanations inside. This doesn't fix the issue for dirstate-v1, a later patch addresses it.