Change Map.center.widget SRID to 4326 as it should be

By default, a PointField uses a OpenLayersWidget, which forces the
SRID to 3857 when casting geojson (no idea why, given geojson SRID
is 4326).

umap/forms.py

@@ -63,7 +63,8 @@ class MapSettingsForm(forms.ModelForm):
 
     def __init__(self, *args, **kwargs):
         super(MapSettingsForm, self).__init__(*args, **kwargs)
-        self.fields["slug"].required = False
+        self.fields['slug'].required = False
+        self.fields['center'].widget.map_srid = 4326
 
     def clean_slug(self):
         slug = self.cleaned_data.get('slug', None)

umap/tests/test_map_views.py

@@ -33,6 +33,8 @@ def test_create(client, user, post_data):
     created_map = Map.objects.latest('pk')
     assert j['id'] == created_map.pk
     assert created_map.name == name
+    assert created_map.center.x == 13.447265624999998
+    assert created_map.center.y == 48.94415123418794
 
 
 def test_map_create_permissions(client, settings):