Add Gr*Proxy classes

src/image/SkImage_Gpu.cpp

 /*
  * Copyright 2012 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkAutoPixmapStorage.h"
 #include "GrCaps.h"
 #include "GrContext.h"
@@ skipping 235 matching lines @@
     SkAutoTUnref<GrTexture> vTex(ctx->textureProvider()->wrapBackendTexture(
         vDesc, kBorrow_GrWrapOwnership));
     if (!yTex || !uTex || !vTex) {
         return nullptr;
     }
 
     const int width = yuvSizes[0].fWidth;
     const int height = yuvSizes[0].fHeight;
 
     // Needs to be a render target in order to draw to it for the yuv->rgb conversion.
-    sk_sp<GrDrawContext> drawContext(ctx->newDrawContext(GrContext::kTight_BackingFit,
+    sk_sp<GrDrawContext> drawContext(ctx->newDrawContext(SkBackingFit::kExact,
                                                          width, height,
                                                          kRGBA_8888_GrPixelConfig,
                                                          0,
                                                          origin));
     if (!drawContext) {
         return nullptr;
     }
 
     GrPaint paint;
     paint.setPorterDuffXPFactory(SkXfermode::kSrc_Mode);
@@ skipping 182 matching lines @@
         return nullptr;
     }
 
     const SkIRect srcR = SkIRect::MakeWH(desc.fWidth, desc.fHeight);
     const SkIPoint dstP = SkIPoint::Make(0, 0);
     ctx->copySurface(dst, src, srcR, dstP);
     ctx->flushSurfaceWrites(dst);
     return dst;
 }