title: what is relation between masksToBounds and cornerRadius?
body: <p>My scroll has some views that is <code>cornerRadius = 10.0</code> and <code>masksToBounds = YES</code>.</p>
  
  <p>This causes a performance issue for scrolling my scroll view. Though I tried each view's <code>shouldRasterize</code> is set <code>YES</code>, the issue is not solved.</p>
  
  <p>However, I know the solution for this issue. That is what <code>masksToBound</code> is set <code>NO</code>. (<code>masksToBound's</code> default value is NO)
  Although <code>masksToBound</code> is <code>NO</code>, my views's corners still have curve and the performance issue is solved, too.</p>
  
  <p>I want to know about relation between <code>cornerRadius</code> and <code>masksToBounds</code>. I'm afraid of unexpected issues with this setting.</p>
  
  <p>Thank you.</p>