Add resource provider flag to avoid client-side buffers

src/gpu/GrGpu.h

 /*
  * Copyright 2011 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #ifndef GrGpu_DEFINED
 #define GrGpu_DEFINED
 
@@ skipping 119 matching lines @@
      * Implements GrTextureProvider::wrapBackendRenderTarget
      */
     GrRenderTarget* wrapBackendRenderTarget(const GrBackendRenderTargetDesc&, GrWrapOwnership);
 
     /**
      * Implements GrTextureProvider::wrapBackendTextureAsRenderTarget
      */
     GrRenderTarget* wrapBackendTextureAsRenderTarget(const GrBackendTextureDesc&);
 
     /**
-     * Creates a buffer.
+     * Creates a buffer in GPU memory. For a client-side buffer use GrBuffer::CreateCPUBacked.
      *
      * @param size            size of buffer to create.
      * @param intendedType    hint to the graphics subsystem about what the buffer will be used for.
      * @param accessPattern   hint to the graphics subsystem about how the data will be accessed.
      * @param data            optional data with which to initialize the buffer.
      *
      * @return the buffer if successful, otherwise nullptr.
      */
     GrBuffer* createBuffer(size_t size, GrBufferType intendedType, GrAccessPattern accessPattern,
                            const void* data = nullptr);
@@ skipping 447 matching lines @@
     SkSTArray<1, MultisampleSpecs, true>   fMultisampleSpecs;
     // The context owns us, not vice-versa, so this ptr is not ref'ed by Gpu.
     GrContext*                             fContext;
 
     friend class GrPathRendering;
     friend class gr_instanced::InstancedRendering;
     typedef SkRefCnt INHERITED;
 };
 
 #endif