flag to use const& instead of const* for src-rect

gm/bitmaprecttest.cpp

 /*
  * Copyright 2013 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"
 #include "SkCanvas.h"
 #include "SkPath.h"
@@ skipping 25 matching lines @@
 //
 static void test_bitmaprect(SkCanvas* canvas) {
     SkBitmap bm;
     make_bm(&bm);
 
     canvas->drawBitmap(bm, 150, 45, NULL);
 
     SkScalar scale = 0.472560018f;
     canvas->save();
     canvas->scale(scale, scale);
-    canvas->drawBitmapRect(bm, SkRect::MakeXYWH(100, 100, 128, 128));
+    canvas->drawBitmapRect(bm, SkRect::MakeXYWH(100, 100, 128, 128), nullptr);
     canvas->restore();
 
     canvas->scale(-1, 1);
     canvas->drawBitmap(bm, -310, 45, NULL);
 }
 
 class BitmapRectTestGM : public skiagm::GM {
 public:
     BitmapRectTestGM() {
 
@@ skipping 12 matching lines @@
         test_bitmaprect(canvas);
     }
 
 private:
     typedef skiagm::GM INHERITED;
 };
 
 //////////////////////////////////////////////////////////////////////////////
 
 DEF_GM( return new BitmapRectTestGM; )