Scans repo projects by longest path match first, rather than shortest.

This makes scan_repo_projects find the correct project even if
multiple projects share a path prefix (e.g. system/foo and
system/foo/bar).

Runtime was barely affected, still a couple of seconds.

Test: treble_manifest_split_test
Change-Id: Ief5c66eec175c7f9f7d5e7ea662a2b7d16de9e48
1 file changed