Fixed #7350, #7202 -- Fixed serialization for multi-model inheritance, which had multiple problems:

* Serializers were including all superclass fields in their output. Now only local fields are included.
 * Implicit OneToOne primary keys were not correctly added to the metamodel, so they were always marked to be serialized, even though they were primary
 * Model saving was too aggressive about creating new parent class instances during deserialization. Raw save on a model now skips saving of the parent class.

git-svn-id: http://code.djangoproject.com/svn/django/trunk@7600 bcc190cf-cafb-0310-a4f2-bffc1f526a37

tests/modeltests/model_inheritance/models.py

@@ -147,8 +147,13 @@ Test constructor for Restaurant.
 >>> c.save()
 >>> ir = ItalianRestaurant(name='Ristorante Miron', address='1234 W. Ash', serves_hot_dogs=False, serves_pizza=False, serves_gnocchi=True, rating=4, chef=c)
 >>> ir.save()
+>>> ItalianRestaurant.objects.filter(address='1234 W. Ash')
+[<ItalianRestaurant: Ristorante Miron the italian restaurant>]
+
 >>> ir.address = '1234 W. Elm'
 >>> ir.save()
+>>> ItalianRestaurant.objects.filter(address='1234 W. Elm')
+[<ItalianRestaurant: Ristorante Miron the italian restaurant>]
 
 # Make sure Restaurant and ItalianRestaurant have the right fields in the right
 # order.