See the discussion in CASSANDRA-6887 on why.
Sylvain: "instead of having read_repair_chance=0.1 and dclocal_read_repair_chance=0, to switch to read_repair_chance=0 and dclocal_read_repair_chance=0.1. If you have only one DC, then it won't change from the current default, and if you have multiple-DC, I can agree that not crossing DC boundaries for read repair is a better default."
Not basing on 1.2 because it's rather late for that. Not too late for the 2.0 cycle though, so setting fixver to 2.0.9.