[stdlib] String.init(data: NSData, encoding: UInt)
[stdlib] String.init(data: NSData, encoding: UInt)

Fixes <rdar://19872780>

Swift SVN r31191

apple/swift-corelibs-foundation,apple/swift-corelibs-foundation,apple/swift-corelibs-foundation,apple/swift-corelibs-foundation,apple/swift-corelibs-foundation