Tag build swift-DEVELOPMENT-SNAPSHOT-2016-10-02-a
Merge remote-tracking branch 'origin/swift-3.1-branch' into stable
* origin/swift-3.1-branch:
[Coverage] Clarify a function contract (NFC)
[llvm-cov] Factor out logic to remove unmapped inputs (NFC)
[llvm-cov] Filter away source files that aren't in the coverage mapping
[llvm-cov] Get rid of all invalid filename references
[llvm-cov] Minor cleanup. NFC.
[llvm-cov] Document some fields in a class (NFC)
[llvm-cov] Add the ability to specify directories of input source files
[llvm-cov] Demangle names for hidden instantiation views
