Convert GrClip to an abstract base class

src/effects/SkBlurMaskFilter.cpp

 /*
  * Copyright 2006 The Android Open Source Project
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkBlurMaskFilter.h"
 #include "SkBlurMask.h"
 #include "SkGpuBlurUtils.h"
@@ skipping 1259 matching lines @@
             //             = src + (1 - src) * dst
             paint.setCoverageSetOpXPFactory(SkRegion::kUnion_Op);
         } else if (kOuter_SkBlurStyle == fBlurStyle) {
             // outer:  dst = dst * (1 - src)
             //             = 0 * src + (1 - src) * dst
             paint.setCoverageSetOpXPFactory(SkRegion::kDifference_Op);
         } else {
             paint.setCoverageSetOpXPFactory(SkRegion::kReplace_Op);
         }
 
-        drawContext->drawRect(GrClip::WideOpen(), paint, SkMatrix::I(), clipRect);
+        drawContext->drawRect(GrWideOpenClip(), paint, SkMatrix::I(), clipRect);
     }
 
     *result = drawContext->asTexture().release();
     return true;
 }
 
 #endif // SK_SUPPORT_GPU
 
 
 #ifndef SK_IGNORE_TO_STRING
@@ skipping 21 matching lines @@
     } else {
         str->append("None");
     }
     str->append("))");
 }
 #endif
 
 SK_DEFINE_FLATTENABLE_REGISTRAR_GROUP_START(SkBlurMaskFilter)
     SK_DEFINE_FLATTENABLE_REGISTRAR_ENTRY(SkBlurMaskFilterImpl)
 SK_DEFINE_FLATTENABLE_REGISTRAR_GROUP_END