use ClipOp instead of SkRegion for clipping

tests/PictureBBHTest.cpp

 /*
  * Copyright 2014 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkCanvas.h"
 #include "SkBBoxHierarchy.h"
 #include "SkPaint.h"
@@ skipping 65 matching lines @@
 // Test to verify the playback of a picture into a canvas that has
 // an empty clip.
 //
 class EmptyClipPictureBBHTest : public PictureBBHTestBase {
 public:
     EmptyClipPictureBBHTest() 
         : PictureBBHTestBase(2, 2, 3, 3) { }
 
     virtual void doTest(SkCanvas& playbackCanvas, SkCanvas& recordingCanvas) SK_OVERRIDE {
         // intersect with out of bounds rect -> empty clip.
-        playbackCanvas.clipRect(SkRect::MakeXYWH(SkIntToScalar(10), SkIntToScalar(10),
-            SkIntToScalar(1), SkIntToScalar(1)), SkRegion::kIntersect_Op);
+        playbackCanvas.clipRect(SkRect::MakeXYWH(10, 10, 1, 1));
         SkPaint paint;
-        recordingCanvas.drawRect(SkRect::MakeXYWH(SkIntToScalar(0), SkIntToScalar(0),
-            SkIntToScalar(3), SkIntToScalar(3)), paint);
+        recordingCanvas.drawRect(SkRect::MakeWH(3, 3), paint);
     }
 
     virtual ~EmptyClipPictureBBHTest() { }
 };
 
 DEF_TEST(PictureBBH, reporter) {
 
     DrawEmptyPictureBBHTest emptyPictureTest;
     emptyPictureTest.run(reporter);
 
@@ skipping 24 matching lines @@
 DEF_TEST(PictureBBH_Clear, r) {
     test_clear(r, NULL);
 
     SkTileGridFactory::TileGridInfo grid = { {1,1}, {0,0}, {0,0} };
     SkTileGridFactory tilegrid(grid);
     test_clear(r, &tilegrid);
 
     SkRTreeFactory rtree;
     test_clear(r, &rtree);
 }