[MERGE][#354036] Server-side (sink-side) fix for missing inventory parents

[Robert Collins]

Robert Collins has voted comment.
Status is now: Semi-approved
Comment:
I may be misreading it but this seems like it will reprocess a bunch of 
data we've already processed.

Wouldn't it be much better to accumulate the references as data comes 
through?

For details, see: 
http://bundlebuggy.aaronbentley.com/project/bzr/request/%3C20090417141519.GA9721%40steerpike.home.puzzling.org%3E
Project: Bazaar