use gpu surface to match canvas
use gpu surface to match canvas

change gm to reset shader when we start antialiasing



git-svn-id: e8541e15acce502a64c929015570ad1648e548cd@6448 2bbb7eff-a529-9590-31e7-b0007b416f81

Cue/skia,Cue/skia,Cue/skia,Cue/skia