Add support for creating texture backed images where Skia will delete the texture.

include/gpu/GrTextureProvider.h

 /*
  * Copyright 2015 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #ifndef GrTextureProvider_DEFINED
 #define GrTextureProvider_DEFINED
 
@@ skipping 88 matching lines @@
 
     ///////////////////////////////////////////////////////////////////////////
     // Wrapped Backend Surfaces
 
     /**
      * Wraps an existing texture with a GrTexture object.
      *
      * OpenGL: if the object is a texture Gr may change its GL texture params
      *         when it is drawn.
      *
-     * @param  desc     description of the object to create.
-     *
      * @return GrTexture object or NULL on failure.
      */
-    GrTexture* wrapBackendTexture(const GrBackendTextureDesc& desc);
+    GrTexture* wrapBackendTexture(const GrBackendTextureDesc& desc,
+                                  GrWrapOwnership = kBorrow_GrWrapOwnership);
 
     /**
      * Wraps an existing render target with a GrRenderTarget object. It is
      * similar to wrapBackendTexture but can be used to draw into surfaces
      * that are not also textures (e.g. FBO 0 in OpenGL, or an MSAA buffer that
-     * the client will resolve to a texture).
-     *
-     * @param  desc     description of the object to create.
+     * the client will resolve to a texture). Currently wrapped render targets
+     * always use the kBorrow_GrWrapOwnership semantics.
      *
      * @return GrTexture object or NULL on failure.
      */
      GrRenderTarget* wrapBackendRenderTarget(const GrBackendRenderTargetDesc& desc);
 
 protected:
     GrTextureProvider(GrGpu* gpu, GrResourceCache* cache) : fCache(cache), fGpu(gpu) {}
 
     /**
      * Assigns a unique key to a resource. If the key is associated with another resource that
@@ skipping 32 matching lines @@
     bool isAbandoned() const {
         SkASSERT(SkToBool(fGpu) == SkToBool(fCache));
         return !SkToBool(fCache);
     }
 
     GrResourceCache* fCache;
     GrGpu* fGpu;
 };
 
 #endif