Convert GrClip to an abstract base class

src/effects/SkGpuBlurUtils.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 "SkGpuBlurUtils.h"
 
 #include "SkRect.h"
@@ skipping 178 matching lines @@
     } else {
         srcRect = localDstBounds;
     }
 
     scale_rect(&srcRect, 1.0f / scaleFactorX, 1.0f / scaleFactorY);
     srcRect.roundOut(&srcRect);
     scale_rect(&srcRect, static_cast<float>(scaleFactorX),
                          static_cast<float>(scaleFactorY));
 
     // setup new clip
-    GrClip clip(localDstBounds);
+    GrFixedClip clip;
+    clip.resetNonAA(localDstBounds);
 
     sk_sp<GrTexture> srcTexture(sk_ref_sp(origSrc));
 
     SkASSERT(kBGRA_8888_GrPixelConfig == srcTexture->config() ||
              kRGBA_8888_GrPixelConfig == srcTexture->config() ||
              kSRGBA_8888_GrPixelConfig == srcTexture->config() ||
              kSBGRA_8888_GrPixelConfig == srcTexture->config() ||
              kAlpha_8_GrPixelConfig == srcTexture->config());
 
     const int width = SkScalarFloorToInt(dstBounds.width());
@@ skipping 148 matching lines @@
         srcDrawContext = dstDrawContext;
         srcRect = dstRect;
         dstDrawContext.swap(tmpDrawContext);
     }
 
     return srcDrawContext;
 }
 #endif
 
 }