title: LAContext.canEvaluatePolicy returns true when TouchID is locked out on iOS 9
body: <p>I was playing around with LocalAuthentication on iOS 9 and iOS 10. And noticed the following difference in behavior. In iOS 9, if I execute the code shown below, and cause the touchID to get locked out by using the wrong finger to authenticate, the call context.canEvaluatePolicy returns true even after Touch ID has been locked out, and then the call to context.evaluatePolicy causes the device to prompt me for the device passcode.</p>
  
  <p>In iOS 10, if I lockout TouchID, canEvaluatePolicy returns false, and the error is has a code indicating TouchIDLockout.</p>
  
  <p>TouchIDLockout was introduced in iOS 9, so I would expect to get that error code in iOS 9, but as yet have not. Has anyone else experienced this?</p>
  
  <pre><code>@IBAction func test(_ sender : UIButton) {
      let context = LAContext()
      var error : NSError? = nil
      if  context.canEvaluatePolicy(.deviceOwnerAuthenticationWithBiometrics, error: &amp;error) {
              context.evaluatePolicy(.deviceOwnerAuthenticationWithBiometrics, localizedReason: "Boom", reply: { (success, error) in
                  let code = (error as? LAError)?.code.rawValue
                  sender.setTitle(String(code ?? 2), for: .normal)
              })
          }
      }
  
  }
  </code></pre>
  
  <p>}</p>