[MERGE][bug 115947] Fix DirState.set_state_from_inventory() for paths with common prefixes

[John Arbash Meinel]

John Arbash Meinel has voted +1.
Status is now: Semi-approved
Comment:
Can i get this reviewed? I believe it fixes a couple of bugs relating to 
anything that calls _write_inventory. (rename_one, remove, etc)

For details, see: 
http://bundlebuggy.aaronbentley.com/request/%3C46518633.5090609%40arbash-meinel.com%3E