[1.11.x] Refs #25809 -- Omitted pages_per_range from BrinIndex.deconstruct() if it's None.

Backport of fb42d02471 from master

django/contrib/postgres/indexes.py

@@ -31,7 +31,8 @@ class BrinIndex(Index):
 
     def deconstruct(self):
         path, args, kwargs = super(BrinIndex, self).deconstruct()
-        kwargs['pages_per_range'] = self.pages_per_range
+        if self.pages_per_range is not None:
+            kwargs['pages_per_range'] = self.pages_per_range
         return path, args, kwargs
 
     def get_sql_create_template_values(self, model, schema_editor, using):

docs/releases/1.11.5.txt

@@ -26,3 +26,6 @@ Bugfixes
 
 * Added POST request support to ``LogoutView``, for equivalence with the
   function-based ``logout()`` view (:ticket:`28513`).
+
+* Omitted ``pages_per_range`` from ``BrinIndex.deconstruct()`` if it's ``None``
+  (:ticket:`25809`).

tests/postgres_tests/test_indexes.py

@@ -39,7 +39,7 @@ class BrinIndexTests(PostgreSQLTestCase):
         path, args, kwargs = index.deconstruct()
         self.assertEqual(path, 'django.contrib.postgres.indexes.BrinIndex')
         self.assertEqual(args, ())
-        self.assertEqual(kwargs, {'fields': ['title'], 'name': 'test_title_brin', 'pages_per_range': None})
+        self.assertEqual(kwargs, {'fields': ['title'], 'name': 'test_title_brin'})
 
     def test_deconstruction_with_pages_per_range(self):
         index = BrinIndex(fields=['title'], name='test_title_brin', pages_per_range=16)