add peekPixels to canvas

gm/imagefiltersclipped.cpp

Index: gm/imagefiltersclipped.cpp
diff --git a/gm/imagefiltersclipped.cpp b/gm/imagefiltersclipped.cpp
index 82873ab3729df60748218dd288d25f9b9b7f92bf..4e427298aae57a50fee71a8e975fff5df2e81f82 100644
--- a/gm/imagefiltersclipped.cpp
+++ b/gm/imagefiltersclipped.cpp
@@ -35,8 +35,7 @@ protected:
 
     void make_checkerboard() {
         fCheckerboard.allocN32Pixels(64, 64);
-        SkBitmapDevice device(fCheckerboard);
-        SkCanvas canvas(&device);
+        SkCanvas canvas(fCheckerboard);
         canvas.clear(0x00000000);
         SkPaint darkPaint;
         darkPaint.setColor(0xFF404040);
@@ -60,8 +59,7 @@ protected:
         SkScalar y = SkIntToScalar(height / 2);
         SkScalar radius = SkScalarMul(SkMinScalar(x, y), SkIntToScalar(4) / SkIntToScalar(5));
         fGradientCircle.allocN32Pixels(width, height);
-        SkBitmapDevice device(fGradientCircle);
-        SkCanvas canvas(&device);
+        SkCanvas canvas(fGradientCircle);

[bsalomon, 2014/02/12 15:56:37]

is the spacing really weird or is this just a codereview artifact? anyway, it'd
be nice to clean it up while we're modifying this. I seem similar odd whitespace
in files below with similar code...

[reed1, 2014/02/12 17:24:10]

artifact I think

         canvas.clear(0x00000000);
         SkColor colors[2];
         colors[0] = SK_ColorWHITE;