2. Pass NSString? to thunk, not String?
3. Use proper Objective-C out parameter coding practices
4. Use correct nullability decorator in thunk for backupItemName parameter
rdar://problem/28755011
From the Swift documentation:
"If you define an optional variable without providing a default value,
the variable is automatically set to nil for you."
Addresses the following issues:
rdar://problem/25992816 -[NSUserDefaults registerDefaults] is being imported as NSUserDefaults.register(), which is confusing
rdar://problem/26291437 UserDefaults has 'setURL(forKey:)' instead of 'set(_:forKey:)'
rdar://problem/26375229 FileManager overlay has old naming
rdar://problem/26090891 NSBundle methods that are overridden in the apinotes incorrectly handle the first argument pattern
rdar://problem/26271340 struct URL initializer for fileURLWithFileSystemRepresentation is incorrectly named'
rdar://problem/26443640 XMLDTDNode.Kind conflicts with XMLNode.Kind and should be renamed to XMLDTDNode.DTDKind
rdar://problem/26500390 registerUndoWithTarget in overlay not updated for new API names
rdar://problem/26653451 NSCoder encodeDataObject is misleading
rdar://problem/26653653 NSCoder decodeObjectOfClass is redundant
rdar://problem/26653694 NSCoder.decodeTopLevelObjectForKey does not follow naming guidelines
rdar://problem/26656299 SocketNativeHandle should be a hoisted type to SocketPort
https://bugs.swift.org/browse/SR-1903
