[Success!] [MERGE] Improve tests for the behaviour of Tree.iter_changes for missing paths that are only present in one tree, and fix found bugs. (Robert Collins)

[Bundle Buggy]

This change has been merged.
Previous status: Conditionally approved

For details, see: 
http://bundlebuggy.aaronbentley.com/project/bzr/request/%3C1218597717.4514.416.camel%40lifeless-64%3E
Project: Bazaar