Make sure that not deleting the service_users doesn't leave them stale

app/models/services/facebook.rb

@@ -47,6 +47,6 @@ class Services::Facebook < Service
       su.attach_local_models
       su
     }
-    ServiceUser.import(data)
+    ServiceUser.import(data, :on_duplicate_key_update => [:updated_at, :contact_id, :person_id, :request_id, :invitation_id, :photo_url, :name])
   end
 end

spec/models/services/facebook_spec.rb

@@ -71,6 +71,18 @@ JSON
         @service.save_friends
         @service.service_users.first.person.should == @user2.person
       end
+
+      it 'overwrites local model information' do
+        @service.save_friends
+        su = @service.service_users.first
+        su.person.should == @user2.person
+        su.contact.should == nil
+
+        connect_users_with_aspects(alice, @user2)
+        @service.save_friends
+        su.person.should == @user2.person
+        su.reload.contact.should == alice.contact_for(@user2.person)
+      end
     end
 
     describe '#finder' do