[1.7.x] Fixed #22487: Optional rollback emulation for migrated apps

Conflicts:
	django/db/backends/creation.py
	django/test/runner.py
	docs/ref/settings.txt
	docs/topics/testing/advanced.txt

tests/migration_test_data_persistence/tests.py

@@ -0,0 +1,33 @@
+from django.test import TransactionTestCase
+from .models import Book
+
+
+class MigrationDataPersistenceTestCase(TransactionTestCase):
+    """
+    Tests that data loaded in migrations is available if we set
+    serialized_rollback = True.
+    """
+
+    available_apps = ["migration_test_data_persistence"]
+    serialized_rollback = True
+
+    def test_persistence(self):
+        self.assertEqual(
+            Book.objects.count(),
+            1,
+        )
+
+
+class MigrationDataNoPersistenceTestCase(TransactionTestCase):
+    """
+    Tests the failure case
+    """
+
+    available_apps = ["migration_test_data_persistence"]
+    serialized_rollback = False
+
+    def test_no_persistence(self):
+        self.assertEqual(
+            Book.objects.count(),
+            0,
+        )