[1.11.x] Fixed #27939 -- Updated OpenLayersWidget.map_srid for OpenLayers 3.

Regression in 2ebfda38e6 (refs #25004).

Backport of 93eca976c1 from master

django/contrib/gis/forms/widgets.py

@@ -78,6 +78,7 @@ class BaseGeometryWidget(Widget):
 
 class OpenLayersWidget(BaseGeometryWidget):
     template_name = 'gis/openlayers.html'
+    map_srid = 3857
 
     class Media:
         css = {
@@ -102,7 +103,6 @@ class OSMWidget(OpenLayersWidget):
     template_name = 'gis/openlayers-osm.html'
     default_lon = 5
     default_lat = 47
-    map_srid = 3857
 
     def __init__(self, attrs=None):
         super(OSMWidget, self).__init__()

tests/gis_tests/test_geoforms.py

@@ -116,7 +116,7 @@ class GeometryFieldTest(SimpleTestCase):
         # ordering of the rendered dictionary.
         pt1_serialized = re.search(r'<textarea [^>]*>({[^<]+})<', output).groups()[0]
         pt1_json = json.loads(pt1_serialized.replace('&quot;', '"'))
-        self.assertEqual(pt1_json, {'coordinates': [7.3, 44.0], 'type': 'Point'})
+        self.assertEqual(pt1_json, {'coordinates': [812632.2827908975, 5465442.183322753], 'type': 'Point'})
 
         self.assertInHTML(
             '<textarea id="id_pt2" class="vSerializedField required" cols="150"'
@@ -200,7 +200,7 @@ class SpecializedFieldTest(SimpleTestCase):
         self.assertTrue(form_instance.is_valid())
         rendered = form_instance.as_p()
         self.assertIn('new MapWidget(options);', rendered)
-        self.assertIn('map_srid: 4326,', rendered)
+        self.assertIn('map_srid: 3857,', rendered)
         self.assertIn('gis/js/OLMapWidget.js', str(form_instance.media))
 
     def assertTextarea(self, geom, rendered):
@@ -208,7 +208,9 @@ class SpecializedFieldTest(SimpleTestCase):
 
         self.assertIn('<textarea ', rendered)
         self.assertIn('required', rendered)
-        self.assertIn(escape(geom.json), rendered)
+        ogr = geom.ogr
+        ogr.transform(3857)
+        self.assertIn(escape(ogr.json), rendered)
 
     # map_srid in operlayers.html template must not be localized.
     @override_settings(USE_L10N=True, USE_THOUSAND_SEPARATOR=True)