Commit Graph has misplaced node off top of scroll area

Changeset seems to be missing from CommonSchema.E_BRANCH_TO_DESCENDANT_CS_POSITION even when it is associated with that branch

This causes in the commit graph the changeset either to not be returned or if it is deeplinked positioned incorrectly

Example:

Repo: git://github.com/37signals/prototype.git

csid: 8c2873f07f7fd2c72ee81a5147647dc0e0f8c13e

branch set:
master, rewrite, caja, experimental