[1.7.x] Fixed #22979 -- Moved bug* tests

Backport of 11181a64f from master.

tests/model_forms/models.py

@@ -406,3 +406,19 @@ class Character(models.Model):
 class StumpJoke(models.Model):
     most_recently_fooled = models.ForeignKey(Character, limit_choices_to=today_callable_dict, related_name="+")
     has_fooled_today = models.ManyToManyField(Character, limit_choices_to=today_callable_q, related_name="+")
+
+
+# Model for #639
+class Photo(models.Model):
+    title = models.CharField(max_length=30)
+    image = models.FileField(storage=temp_storage, upload_to='tests')
+
+    # Support code for the tests; this keeps track of how many times save()
+    # gets called on each instance.
+    def __init__(self, *args, **kwargs):
+        super(Photo, self).__init__(*args, **kwargs)
+        self._savecount = 0
+
+    def save(self, force_insert=False, force_update=False):
+        super(Photo, self).save(force_insert, force_update)
+        self._savecount += 1