Upgrade SkSpecialImage to have getTextureRef & getROPixels entry points

src/gpu/GrLayerHoister.cpp

 /*
  * Copyright 2014 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "GrLayerCache.h"
 #include "GrLayerHoister.h"
 #include "GrRecordReplaceDraw.h"
@@ skipping 300 matching lines @@
 
     SkIPoint offset = SkIPoint::Make(0, 0);
     sk_sp<SkSpecialImage> result(layer->filter()->filterImage(img.get(),
                                                               filterContext,
                                                               &offset));
     if (!result) {
         // Filtering failed. Press on with the unfiltered version.
         return;
     }
 
-    SkASSERT(result->peekTexture());
-    layer->setTexture(result->peekTexture(), result->subset(), false);
+    SkASSERT(result->isTextureBacked());
+    SkAutoTUnref<GrTexture> texture(result->asTextureRef(context));
+    layer->setTexture(texture, result->subset(), false);
     layer->setOffset(offset);
 }
 
 void GrLayerHoister::DrawLayers(GrContext* context, const SkTDArray<GrHoistedLayer>& layers) {
     for (int i = 0; i < layers.count(); ++i) {
         GrCachedLayer* layer = layers[i].fLayer;
         const SkBigPicture* pict = layers[i].fPicture->asSkBigPicture();
         if (!pict) {
             // TODO: can we assume / assert this?
             continue;
@@ skipping 56 matching lines @@
 #if !GR_CACHE_HOISTED_LAYERS
 
     // This code completely clears out the atlas. It is required when
     // caching is disabled so the atlas doesn't fill up and force more
     // free floating layers
     layerCache->purgeAll();
 #endif
 
     layerCache->end();
 }