Fix closure return type

Author: aschwaighofer

Foundation/NSDictionary.swift

@@ -483,7 +483,7 @@ open class NSDictionary : NSObject, NSCopying, NSMutableCopying, NSSecureCoding,
         let lock = NSLock()
 
         getObjects(&objects, andKeys: &keys, count: count)
-        withoutActuallyEscaping(block) { (closure: @escaping (Any, Any, UnsafeMutablePointer<ObjCBool>) -> Void) -> (Int) -> Void in
+        withoutActuallyEscaping(block) { (closure: @escaping (Any, Any, UnsafeMutablePointer<ObjCBool>) -> Void) -> () in
             let iteration: (Int) -> Void = { (idx) in
                 lock.lock()
                 var stop = sharedStop

Foundation/NSIndexSet.swift

@@ -389,7 +389,7 @@ open class NSIndexSet : NSObject, NSCopying, NSMutableCopying, NSSecureCoding {
         let lock = NSLock()
         let ranges = _ranges[startRangeIndex...endRangeIndex]
         let rangeSequence = (reverse ? AnyCollection(ranges.reversed()) : AnyCollection(ranges))
-        withoutActuallyEscaping(block) { (closure: @escaping (P, UnsafeMutablePointer<ObjCBool>) -> R) -> (Int) -> Void in
+        withoutActuallyEscaping(block) { (closure: @escaping (P, UnsafeMutablePointer<ObjCBool>) -> R) -> () in
             let iteration = { (rangeIdx) in
                 lock.lock()
                 var stop = ObjCBool(sharedStop)