pytype: stop excluding patch.py

The underlying `email.generator.BytesGenerator` is documented as requiring an
`fp` that accepts bytes, so I'm not sure why pytype is getting confused:

  File "/mnt/c/Users/Matt/hg/mercurial/patch.py", line 112, in msgfp:
      Function Generator.__init__ was called with the wrong arguments [wrong-arg-types]
           Expected: (self, outfp: TextIO, ...)
    Actually passed: (self, outfp: io.BytesIO, ...)

Differential Revision: https://phab.mercurial-scm.org/D11922

mercurial/patch.py

@@ -109,7 +109,9 b' def split(stream):'
     def mimesplit(stream, cur):
         def msgfp(m):
             fp = stringio()
+            # pytype: disable=wrong-arg-types
             g = mail.Generator(fp, mangle_from_=False)
+            # pytype: enable=wrong-arg-types
             g.flatten(m)
             fp.seek(0)
             return fp

tests/test-check-pytype.t

@@ -26,7 +26,6 b' mercurial/keepalive.py # [attribu'
 mercurial/localrepo.py        # [attribute-error]
 mercurial/manifest.py         # [unsupported-operands], [wrong-arg-types]
 mercurial/minirst.py          # [unsupported-operands], [attribute-error]
-mercurial/patch.py            # [wrong-arg-types]
 mercurial/pure/osutil.py      # [invalid-typevar], [not-callable]
 mercurial/pure/parsers.py     # [attribute-error]
 mercurial/pycompat.py         # bytes vs str issues
@@ -65,7 +64,6 b' development, but may be a hinderance for'
   >    -x mercurial/localrepo.py \
   >    -x mercurial/manifest.py \
   >    -x mercurial/minirst.py \
-  >    -x mercurial/patch.py \
   >    -x mercurial/pure/osutil.py \
   >    -x mercurial/pure/parsers.py \
   >    -x mercurial/pycompat.py \