Simplify autoCloseCommits() handling of exact SHA-1 matches

Ref objects inside of the byCommit map cannot be null.
The ref != null test is always true, and can be dropped.

While we are cleaning up this code, inline the Set<Ref>
that is used only for the loop control.

Change-Id: I8fc9a62672b94203ababf8f5b529ded727cf700a
1 file changed