tree b0255c4465a9a8db0b0dd22b52c08b55070f8980
parent 3d67ed56c610747aa8ed52fdc830bc4cef5f03b7
author Dave Borowitz <dborowitz@google.com> 1370888284 -0700
committer Dave Borowitz <dborowitz@google.com> 1370890785 -0700

Reuse visibility check of revision when checking old revision

The most typical revision/old revision pair is foo and foo^. Since we
just checked that foo is reachable, reuse this information when
checking that foo^ is reachable.

Change-Id: I689ace9acfb248689f3893c4e77b8e87a6341c3f