The plain scaling is rather rough, and in fact drawing a scaled bitmap
the normal way gives much better results (because OutputDevice pre-scales
the bitmap before it's drawn). This one may be a bit slow perhaps,
but hopefully nobody there's no code that'd extensively use bitmap
drawing with custom transformations (wishful thinking).

Change-Id: I83e05307adfaeac0ed0757f1a0b2603f64caf8f8