[1.1.X] Fixed #12057 -- Corrected regression of caching performance when a model contained a callable default. Thanks to Michael Thornhill for the excellent assistance tracking this problem.

Backport of r11681 from trunk.

git-svn-id: http://code.djangoproject.com/svn/django/branches/releases/1.1.X@11682 bcc190cf-cafb-0310-a4f2-bffc1f526a37

tests/regressiontests/cache/models.py

@@ -0,0 +1,11 @@
+from django.db import models
+from datetime import datetime
+
+def expensive_calculation():
+    expensive_calculation.num_runs += 1
+    return datetime.now()
+
+class Poll(models.Model):
+    question = models.CharField(max_length=200)
+    answer = models.CharField(max_length=200)
+    pub_date = models.DateTimeField('date published', default=expensive_calculation)