allow clip calls w/o op param, remove unnecessary kReplace ops

gm/bigblurs.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 "SkBlurMask.h"
 #include "SkBlurMaskFilter.h"
@@ skipping 62 matching lines @@
                 blurPaint.setMaskFilter(SkBlurMaskFilter::Make((SkBlurStyle)j, kSigma));
 
                 for (int k = 0; k < (int)SK_ARRAY_COUNT(origins); ++k) {
                     canvas->save();
 
                     SkRect clipRect = SkRect::MakeXYWH(SkIntToScalar(desiredX),
                                                        SkIntToScalar(desiredY),
                                                        SkIntToScalar(kCloseUpSize),
                                                        SkIntToScalar(kCloseUpSize));
 
-                    canvas->clipRect(clipRect, SkCanvas::kReplace_Op, false);
+                    canvas->clipRect(clipRect);
 
                     canvas->translate(desiredX-origins[k].fX,
                                       desiredY-origins[k].fY);
 
                     if (0 == i) {
                         canvas->drawRect(bigRect, blurPaint);
                     } else {
                         canvas->drawPath(rectori, blurPaint);
                     }
                     canvas->restore();
@@ skipping 11 matching lines @@
 private:
     static constexpr int kCloseUpSize = 64;
     static constexpr int kWidth = 5 * kCloseUpSize;
     static constexpr int kHeight = 2 * (kLastEnum_SkBlurStyle + 1) * kCloseUpSize;
 
     typedef GM INHERITED;
 };
 
 DEF_GM(return new BigBlursGM;)
 }