Backport changed from 2.0.0: REQUIRED, 2.1: REQUIRED to 2.0.0: DONE, 2.1: REQUIRED
r42230 and r42231 were backported to ruby_2_0_0 at r45473. These changesets were required for resolv conflict.
And r45360 and r45361 were backported to ruby_2_0_0 at r45474.