Models having gis fields cannot be used with Manager.raw()

[gcbirzan]

This bug was introduced in ​1a85b07bddbf43da00311bdbb3ef5519a3165dc6 (I found it with git bisect). Trying to do this results in:

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ERROR: test_17_raw_query (gis_tests.relatedapp.test_new.RelatedGeoModelTest)
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Traceback (most recent call last):
  File "/home/gcbirzan/PycharmProjects/django/tests/gis_tests/relatedapp/test_new.py", line 10, in test_17_raw_query
    list(raw)
  File "/home/gcbirzan/PycharmProjects/django/django/db/models/query.py", line 1234, in __iter__
    for values in query:
  File "/home/gcbirzan/PycharmProjects/django/django/db/models/sql/compiler.py", line 949, in apply_converters
    value = converter(value, expression, connection)
  File "/home/gcbirzan/PycharmProjects/django/django/contrib/gis/db/backends/postgis/operations.py", line 395, in <lambda>
    return lambda value, expression, connection: None if value is None else GEOSGeometry(read(value))
  File "/home/gcbirzan/PycharmProjects/django/django/contrib/gis/geos/prototypes/io.py", line 153, in read
    return wkb_reader_read_hex(self.ptr, wkb, len(wkb))
  File "/home/gcbirzan/PycharmProjects/django/django/contrib/gis/geos/libgeos.py", line 164, in __call__
    return self.func(*args, **kwargs)
  File "/home/gcbirzan/PycharmProjects/django/django/contrib/gis/geos/prototypes/threadsafe.py", line 55, in __call__
    return self.cfunc(self.thread_context.handle.ptr, *args)
ctypes.ArgumentError: argument 3: <class 'TypeError'>: wrong type

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the test I'm using is:

from django.test import TestCase
from .models import Location


class RelatedGeoModelTest(TestCase):
    fixtures = ['initial']

    def test_17_raw_query(self):
        raw = Location.objects.raw("SELECT * FROM {}".format(Location._meta.db_table))
        list(raw)

This is on python 3.6.3rc1 with libgdal 2.2.1+dfsg-2+b2 (debian sid).