Come to think of it, this optimized method is not so useful,
it could just bring the user misunderstanding and
not to efficient as I expected in the most cases.
So, changed policy for transformation behaviors.
it keeps the properties as others but leaves it to the backend implementation.
Plus, this change contains the correct RenderUpdateFlag.
You can refer the flag in the backend to figure out which kinds of properites has been updated
Change-Id: Ibe0494712598a8161950b9ae2e22ac45bed1c47b
PaintNode -> Paint
ShapeNode -> Shape
SceneNode -> Scene
We can keep clean and neat shorter names.
Change-Id: Ic8521d456d947985e5fbe1ba2bde06faa1f52469
Obivously, we need to clear target before drawing.
Thus canvas request to renderers to clear buffer.
the implementation is upto backend engines.
Change-Id: Ib80da7f2260b021bcfed9fa13fb91c20218f9da0
