title: layoutSubviews being called repeatedly on ios6 after CATransaction
body: <p>I inherited an overly complicated project (so I don't know all of the inner workings), and I'm running into a bug. Certain parts of my app have  some long animations done with CATransaction, and it seems to be causing layoutSubviews to be called repeatedly while the animations are active. This doesn't happen on ios5 and everything looks correct, but on ios6 it gets called nonstop and interferes with a lot of the layout of the view. The stack trace is all hidden/grayed out, but it does seem to begin with <code>CA::Transaction::commit()</code></p>
  
  <p>Did anything with CATransaction change between ios versions to cause something like this?</p>