add peekPixels to SkCanvas and SkSurface

gm/ninepatchstretch.cpp

 /*
  * Copyright 2011 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "gm.h"
 
 static void make_bitmap(SkBitmap* bitmap, SkIRect* center) {
     const int kFixed = 28;
     const int kStretchy = 8;
     const int kSize = 2*kFixed + kStretchy;
 
     bitmap->allocN32Pixels(kSize, kSize);
-    SkBaseDevice* dev = new SkBitmapDevice(*bitmap);
-
-    SkCanvas canvas(dev);
-    dev->unref();
+    SkCanvas canvas(*bitmap);
     canvas.clear(SK_ColorTRANSPARENT);
 
     SkRect r = SkRect::MakeWH(SkIntToScalar(kSize), SkIntToScalar(kSize));
     const SkScalar strokeWidth = SkIntToScalar(6);
     const SkScalar radius = SkIntToScalar(kFixed) - strokeWidth/2;
 
     center->setXYWH(kFixed, kFixed, kStretchy, kStretchy);
 
     SkPaint paint;
     paint.setAntiAlias(true);
@@ skipping 61 matching lines @@
 private:
     typedef GM INHERITED;
 };
 
 //////////////////////////////////////////////////////////////////////////////
 
 static GM* MyFactory(void*) { return new NinePatchStretchGM; }
 static GMRegistry reg(MyFactory);
 
 }