title: Applying a transformation to UIBezierPath makes drawing disappear
body: <p>maybe this is a stupid question, but I'm trying to apply a transformation to a path as simple as this:</p>
  
  <pre><code>let path = UIBezierPath(rect: CGRect(x: 10, y: 10, width: 20, height: 20))
  path.apply(CGAffineTransform(rotationAngle: 2.0))
  "colorLiteral".setFill()
  path.fill()
  </code></pre>
  
  <p>And seems like the fact of adding the "apply" line, completely erases the shape on the view, whereas if I don't include that line, the shape appears on its place correctly.</p>
  
  <p>I'm quite new at Swift so I guess I'm missing an important step on this?
  Thanks all!</p>