Create GrVkCopyPipeline class

src/gpu/vk/GrVkPipeline.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 GrVkPipeline_DEFINED
 #define GrVkPipeline_DEFINED
 
@@ skipping 25 matching lines @@
     VkPipeline pipeline() const { return fPipeline; }
 
     static void SetDynamicState(GrVkGpu*, GrVkCommandBuffer*, const GrPipeline&);
 
 #ifdef SK_TRACE_VK_RESOURCES
     void dumpInfo() const override {
         SkDebugf("GrVkPipeline: %d (%d refs)\n", fPipeline, this->getRefCnt());
     }
 #endif
 
-private:
+protected:
     GrVkPipeline(VkPipeline pipeline) : INHERITED(), fPipeline(pipeline) {}
 
-    GrVkPipeline(const GrVkPipeline&);
-    GrVkPipeline& operator=(const GrVkPipeline&);
+    VkPipeline  fPipeline;
 
+private:
     void freeGPUData(const GrVkGpu* gpu) const override;
 
-    VkPipeline  fPipeline;
-
     typedef GrVkResource INHERITED;
 };
 
 #endif