Fix handling of tuples in CreateCopyWithNewLayout.

If the layout of a single tensor in a tuple is different from its use, then
CreateCopyWithNewLayout will do a deep copy of the entire tuple.  Not only does
this operation create unnecessary copies of elements where the layout is the
same, it will throw an error if the tuple contains elements like token[] that
cannot be copied.  As a result, layout assignment on TPU occassionally causes
mysterious compilation failures for code that runs correctly on CPU and GPU.

PiperOrigin-RevId: 215615731