Support filtering FileDiffs in the WebAPI by their commit
Review Request #9757 — Created March 7, 2018 and submitted — Latest diff uploaded
FileDifflist resource now supports filtering by a commit ID via
?commit-id=<id>query parameter. Doing so will limit the
FileDiffobjects who are associated with that commit.
Passing an invalid commit ID will result in no results being returned.
Ran unit tests.