title: UIPopoverPresentationController/UIPopoverController loses backgroundColor on interface rotation
body: <p>I've got a menu in iOS that I'm displaying in a popover. I can present a popover in both iOS7 and iOs8 using UIPopoverController and UIPopoverPresentation controllers respectively. I'm running into a problem though that when the popover is visible and the device rotates, the popover disappears for a split second during the animation, then it reappears after the animation. The problem is, when the popover reappears, its background color is drawn as the default background color.</p>
  
  <p>I'm setting the color by using the <code>backgroundColor</code> property.</p>
  
  <pre><code>self.popoverPresentationController.backgroundColor = [UIColor grayColor]; // iOS 8 style
  </code></pre>
  
  <p>I'm 90% sure this is actually a bug in Apple's implementation. The value I see in the <code>backgroundColor</code> after rotation property is correct, but the pixels drawn are not. I wonder if anybody else has experienced this issue and found work arounds. If there is a radar open I'll follow it, if not I'll submit one myself.</p>
  
  <p>I'll add how I am presenting the popover. In both versions I use a barButtonItem as my anchor.</p>
  
  <pre><code>[self.menuPopoverController presentPopoverFromBarButtonItem:item permittedArrowDirections:UIPopoverArrowDirectionAny animated:animated];
  </code></pre>
  
  <p>Here it is using the new iOS8 UIPresentationPopoverController:</p>
  
  <pre><code>UIPopoverPresentationController *popover = self.popoverPresentationController;
  popover.permittedArrowDirections = UIPopoverArrowDirectionAny;
  popover.barButtonItem = item;
  [viewController presentViewController:self animated:YES completion:nil];  // I'm presenting a view controller from within itself.
  </code></pre>