Change NSNumber to initialize with CFNumberCreate()

Author: norio-nomura

Foundation/JSONEncoder.swift

@@ -10,6 +10,8 @@
 //
 //===----------------------------------------------------------------------===//
 
+import CoreFoundation
+
 //===----------------------------------------------------------------------===//
 // JSON Encoder
 //===----------------------------------------------------------------------===//
@@ -1742,7 +1744,7 @@ extension _JSONDecoder {
         }
 
         // TODO: Add a flag to coerce non-boolean numbers into Bools?
-        guard number._objCType == .Bool else {
+        guard number._cfTypeID == CFBooleanGetTypeID() else {
             throw DecodingError._typeMismatch(at: self.codingPath, expectation: type, reality: value)
         }
 

Foundation/NSCFBoolean.swift

@@ -78,7 +78,10 @@ internal class __NSCFBoolean : NSNumber {
     override var objCType: UnsafePointer<Int8> {
         // This must never be fixed to be "B", although that would
         // cause correct old-style archiving when this is unarchived.
-        return UnsafePointer<Int8>(bitPattern: UInt(_NSSimpleObjCType.Char.rawValue.value))!
+        func _objCType(_ staticString: StaticString) -> UnsafePointer<Int8> {
+            return UnsafeRawPointer(staticString.utf8Start).assumingMemoryBound(to: Int8.self)
+        }
+        return _objCType("c")
     }
 
     internal override func _cfNumberType() -> CFNumberType  {