Fix NSKeyedUnarchiver.decodeBool(forKey:) and add test to TestNSPredicate.test_NSCoding()

Author: norio-nomura

Foundation/NSKeyedUnarchiver.swift

@@ -683,10 +683,10 @@ open class NSKeyedUnarchiver : NSCoder {
     }
 
     open override func decodeBool(forKey key: String) -> Bool {
-        guard let result : NSNumber = _decodeValue(forKey: key) else {
+        guard let result : Bool = _decodeValue(forKey: key) else {
             return false
         }
-        return result.boolValue
+        return result
     }
 
     open override func decodeInt32(forKey key: String) -> Int32 {

TestFoundation/TestNSPredicate.swift

@@ -101,6 +101,9 @@ class TestNSPredicate: XCTestCase {
         let predicateA = NSPredicate(value: true)
         let predicateB = NSKeyedUnarchiver.unarchiveObject(with: NSKeyedArchiver.archivedData(withRootObject: predicateA)) as! NSPredicate
         XCTAssertEqual(predicateA, predicateB, "Archived then unarchived uuid must be equal.")
+        let predicateC = NSPredicate(value: false)
+        let predicateD = NSKeyedUnarchiver.unarchiveObject(with: NSKeyedArchiver.archivedData(withRootObject: predicateC)) as! NSPredicate
+        XCTAssertEqual(predicateC, predicateD, "Archived then unarchived uuid must be equal.")
     }
 
     func test_copy() {