title: CAKeyframeAnimation : contents change back to first image when stopped
body: <p>I animate the content of a <code>CALayer</code> using the following code:</p>
  
  <pre><code>CAKeyframeAnimation *countanimation = [CAKeyframeAnimation animation];
  NSArray *images = [NSArray arrayWithObjects:(id)[UIImage imageNamed:@"number3"].CGImage, 
                          (id)[UIImage imageNamed:@"number2"].CGImage, 
                          (id)[UIImage imageNamed:@"number1"].CGImage, nil];
  [countanimation setKeyPath:@"contents"];
  [countanimation setValues:images];
  [countanimation setCalculationMode:kCAAnimationDiscrete];
  [countanimation setDuration:3.0f];
  [countanimation setDelegate:self];
  [countanimation setAutoreverses:NO];
  [countanimation setRemovedOnCompletion:NO];
  [countanimation setValue:@"Countdown" forKey:@"name"];
  [countDown addAnimation:countanimation forKey:nil];
  </code></pre>
  
  <p>And want to hide the layer when the animation is stopped:</p>
  
  <pre><code>- (void)animationDidStop:(CAAnimation *)anim finished:(BOOL)flag
  {
      if([[anim valueForKey:@"name"] isEqual:@"Countdown"])
      {
          [countDown setHidden:YES];
          ...
      }
  }
  </code></pre>
  
  <p>The problem is that the layer is flashing once with the original image (number3) and is hidden after that.</p>
  
  <p>I want to know why the layer goes back to the original even though I set <code>removedOnCompletion</code> to <code>NO</code>.</p>