This means more things:
* Graphic won't swap out itself, so those classes which uses
Graphic without GraphicObject won't need to deal with swapping.
* When a Graphic is queried from GraphicObject the caller won't
need to deal with swapping, because GraphicObject swaps it in
before return.
* GraphicObject will swap in the Graphic always when a swapping
dependent data is queried (e.g. whole graphic, transformed graphic
or AnimationNotifyHdl)

Change-Id: I2bf6e37291ec94146f10aac4a35084682437ed16