* use full window for activities, and shift & clip the content
* refactored the compatibility code, and introdcued Translator class to handle cooridnate translations.
* removed a workaround to handle an activity with configChagne=rotation in old implementation.
* I'll fix background issue on rotation in next CL.
* removed unnecessary scaling code in SurfaceView, which I forgot to remove when I changed SurfaceView
not to scale the content.