Do not use both cumulative and condensed to refer to cumulative diffs

Review Request #7404 — Created June 10, 2015 and submitted — Latest diff uploaded

Information

Review Board
dvcs
c371bb8...

Reviewers

This patch updates the diff comment model and the diff comment resource
to use the term cumulative_diff instead of condensed_diff. The
option was named cumulative_diff in the diff chunk generator and the
diff chunk generator, so this is for consistency.

Ran unit tests.