This change breaks DataList ID generation.  Since you're creating child components before Component:ownerChanged runs, the id of the list isn't set when it goes to create the children, so the children id's aren't prefixed with the parent name.  So, particularly if you have two data lists on the same page, you'll end up with multiple divs with identical ID's like "page0", "page1" etc.  It's super bad to have duplicate ID names, since events won't be dispatched to the correct Control.

IMHO, the orientationChanged makes a lot of brittle assumptions about the create cycle that it shouldn't be.  In practice we never need to switch orientation on the fly, so if you only did it so you could have one sample and be able to switch between them, I'd say the safer thing to do at this point is just make two samples.  Or in the sample, just destroy the one list and create another.