Fix the ChangeSet summary being really slow because we fetch comments on every single file, even ones without comments.
Fix the ChangeSet summary being really slow because we fetch
comments on every single file, even ones without comments.

bk: 511dc7cd2b3wA8dj-a_LVUJi5aECVQ
bitkeeper-scm/bitkeeper,bitkeeper-scm/bitkeeper,bitkeeper-scm/bitkeeper,bitkeeper-scm/bitkeeper,bitkeeper-scm/bitkeeper,bitkeeper-scm/bitkeeper,bitkeeper-scm/bitkeeper,bitkeeper-scm/bitkeeper,bitkeeper-scm/bitkeeper,bitkeeper-scm/bitkeeper,bitkeeper-scm/bitkeeper,bitkeeper-scm/bitkeeper