tests/sitecustomize.py

hgcli: add stub PyOxidizer project

Using commit c772a1379c3026314eda1c8ea244b86c0658951d of
PyOxidizer, I ran `pyoxidizer init-rust-project hgcli` to
create a stub Rust project. The only modifications I made from
what that command produced are:

* Update location of pyembed crate to PyOxidizer's Git repository.
* Removed some trailing whitespace from pyoxidizer.bzl
* Added auto-generated Cargo.lock file

Subsequent commits will modify the stub project to Mercurial's
needs.

Differential Revision: https://phab.mercurial-scm.org/D8350

from __future__ import absolute_import
import os

if os.environ.get('COVERAGE_PROCESS_START'):
    try:
        import coverage
        import uuid

        covpath = os.path.join(
            os.environ['COVERAGE_DIR'], 'cov.%s' % uuid.uuid1()
        )
        cov = coverage.coverage(data_file=covpath, auto_data=True)
        cov._warn_no_data = False
        cov._warn_unimported_source = False
        cov.start()
    except ImportError:
        pass