tree a3c3d055d5ca6ddc4996ecbf1da151ceccce3c0c
parent a0204a4727ce39f3bd1564c445065dce6cefe608
author Ivan Frade <ifrade@google.com> 1574194133 -0800
committer Ivan Frade <ifrade@google.com> 1574357419 -0800

checkNotAdvertisedWants: Be lazy converting Ref to RevCommit

The ref points to an ObjectId that then is translated into a RevCommit.
This translation can be costly and with the incremental reachability
check is probably not needed for most of the elements.

Delay the translation from ObjectId to RevCommit to when it is needed.
Use Streams, that have the laziness built-in, all the way from Ref to
RevCommit.

This should reduce the latency for reachability checks over big sets of
references.

Change-Id: I28693087321b2beff3eaa1f3d2e7840ab0eedc6d
Signed-off-by: Ivan Frade <ifrade@google.com>