Tag build swift-DEVELOPMENT-SNAPSHOT-2017-02-06-a
Merge remote-tracking branch 'origin/swift-4.0-branch' into stable

* origin/swift-4.0-branch:
  Merging r294008: ------------------------------------------------------------------------ r294008 | arphaman | 2017-02-03 06:22:33 -0800 (Fri, 03 Feb 2017) | 14 lines
  Merging r293043: ------------------------------------------------------------------------ r293043 | dergachev | 2017-01-25 02:21:45 -0800 (Wed, 25 Jan 2017) | 12 lines