tests/test-check-pyflakes.t

typing: make the manifest classes known to pytype

These are the same changes as c1d7ac70980b and 45270e286bdc made to dirstate,
for the same reasons.  The migration away from decorating the classes with
`@interfaceutil.implementer` was started back in 3e9a660b074a, but missed one.

#require test-repo pyflakes hg10

  $ . "$TESTDIR/helpers-testrepo.sh"

run pyflakes on all tracked files ending in .py or without a file ending
(skipping binary file random-seed)

  $ cat > test.py <<EOF
  > print(undefinedname)
  > EOF
  $ "$PYTHON" -m pyflakes test.py 2>/dev/null | "$TESTDIR/filterpyflakes.py"
  test.py:1:* undefined name 'undefinedname' (glob)
  
  $ cd "`dirname "$TESTDIR"`"

  $ testrepohg locate 'set:**.py or grep("^#!.*python")' \
  > -X hgext/fsmonitor/pywatchman \
  > -X contrib/python-zstandard \
  > -X mercurial/thirdparty \
  > 2>/dev/null \
  > | xargs "$PYTHON" -m pyflakes 2>/dev/null | "$TESTDIR/filterpyflakes.py"
  contrib/perf.py:*:* undefined name 'xrange' (glob) (?)
  mercurial/pycompat.py:*:* 'codecs' imported but unused (glob)
  mercurial/pycompat.py:*:* 'concurrent.futures' imported but unused (glob)
  mercurial/pycompat.py:*:* 'http.client as httplib' imported but unused (glob)
  mercurial/pycompat.py:*:* 'http.cookiejar as cookielib' imported but unused (glob)
  mercurial/pycompat.py:*:* 'io' imported but unused (glob)
  mercurial/pycompat.py:*:* 'queue' imported but unused (glob)
  mercurial/pycompat.py:*:* 'socketserver' imported but unused (glob)
  mercurial/pycompat.py:*:* 'xmlrpc.client as xmlrpclib' imported but unused (glob)
  mercurial/util.py:*:* 'pickle' imported but unused (glob)