Refactor how we store and use samplers in Ganesh

src/gpu/vk/GrVkPipelineStateDataManager.h

 /*
 * Copyright 2016 Google Inc.
 *
 * Use of this source code is governed by a BSD-style license that can be
 * found in the LICENSE file.
 */
 
 #ifndef GrVkPipelineStateDataManager_DEFINED
 #define GrVkPipelineStateDataManager_DEFINED
 
@@ skipping 41 matching lines @@
     bool uploadUniformBuffers(const GrVkGpu* gpu,
                               GrVkUniformBuffer* vertexBuffer,
                               GrVkUniformBuffer* fragmentBuffer) const;
 private:
     struct Uniform {
         uint32_t fBinding;
         uint32_t fOffset;
         SkDEBUGCODE(
             GrSLType    fType;
             int         fArrayCount;
-            uint32_t    fSetNumber;
         );
     };
 
     template<int N> inline void setMatrices(UniformHandle, int arrayCount,
                                             const float matrices[]) const;
 
     void* getBufferPtrAndMarkDirty(const Uniform& uni) const;
 
     uint32_t fVertexUniformSize;
     uint32_t fFragmentUniformSize;
 
     SkTArray<Uniform, true> fUniforms;
 
     mutable SkAutoMalloc fVertexUniformData;
     mutable SkAutoMalloc fFragmentUniformData;
     mutable bool         fVertexUniformsDirty;
     mutable bool         fFragmentUniformsDirty;
 };
 
 #endif