Add Gr*Proxy classes

src/gpu/GrBlurUtils.cpp

 /*
  * Copyright 2015 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "GrBlurUtils.h"
 #include "GrDrawContext.h"
 #include "GrCaps.h"
@@ skipping 98 matching lines @@
         sampleCnt = 0;
     }
 
     // We actually only need A8, but it often isn't supported as a
     // render target so default to RGBA_8888
     GrPixelConfig config = kRGBA_8888_GrPixelConfig;
     if (context->caps()->isConfigRenderable(kAlpha_8_GrPixelConfig, sampleCnt > 0)) {
         config = kAlpha_8_GrPixelConfig;
     }
 
-    sk_sp<GrDrawContext> drawContext(context->newDrawContext(GrContext::kLoose_BackingFit,
+    sk_sp<GrDrawContext> drawContext(context->newDrawContext(SkBackingFit::kApprox,
                                                              SkScalarCeilToInt(maskRect->width()), 
                                                              SkScalarCeilToInt(maskRect->height()),
                                                              config,
                                                              sampleCnt));
     if (!drawContext) {
         return nullptr;
     }
 
     drawContext->clear(nullptr, 0x0, true);
 
@@ skipping 208 matching lines @@
     }
 
     if (paint.getMaskFilter()) {
         draw_path_with_mask_filter(context, drawContext, clip, &grPaint, viewMatrix,
                                    paint.getMaskFilter(), pathEffect, strokeInfo,
                                    pathPtr, pathIsMutable);
     } else {
         drawContext->drawPath(clip, grPaint, viewMatrix, *pathPtr, strokeInfo);
     }
 }