Tag build swift-DEVELOPMENT-SNAPSHOT-2017-01-24-a
Merge remote-tracking branch 'origin/swift-4.0-branch' into stable

* origin/swift-4.0-branch:
  Merging r292467: ------------------------------------------------------------------------ r292467 | compnerd | 2017-01-18 18:58:46 -0800 (Wed, 18 Jan 2017) | 7 lines
  Merging r292758: ------------------------------------------------------------------------ r292758 | spatel | 2017-01-22 09:06:12 -0800 (Sun, 22 Jan 2017) | 4 lines
  Merging r292323: ------------------------------------------------------------------------ r292323 | pzheng | 2017-01-17 17:03:29 -0800 (Tue, 17 Jan 2017) | 9 lines
  Cherry pick r292625
  Merging r292583: ------------------------------------------------------------------------ r292583 | dannyb | 2017-01-19 22:38:41 -0800 (Thu, 19 Jan 2017) | 4 lines
  Merging r291858 and r291859: ------------------------------------------------------------------------ r291858 | eugenis | 2017-01-12 15:03:03 -0800 (Thu, 12 Jan 2017) | 1 line