Add GrVkCopyPipeline to handle vulkan copies as draws

src/gpu/vk/GrVkCopyManager.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 GrVkCopyManager_DEFINED
+#define GrVkCopyManager_DEFINED
+
+#include "GrVkDescriptorSetManager.h"
+
+#include "vk/GrVkDefines.h"
+
+class GrSurface;
+class GrVkCopyPipeline;
+class GrVkGpu;
+class GrVkUniformBuffer;
+class GrVkVertexBuffer;
+struct SkIPoint;
+struct SkIRect;
+
+class GrVkCopyManager {
+public:
+    GrVkCopyManager()
+        : fVertShaderModule(VK_NULL_HANDLE)
+        , fFragShaderModule(VK_NULL_HANDLE)
+        , fPipelineLayout(VK_NULL_HANDLE)
+        , fUniformBuffer(nullptr) {}
+
+    bool copySurfaceAsDraw(GrVkGpu* gpu,
+                           GrSurface* dst,
+                           GrSurface* src,
+                           const SkIRect& srcRect,
+                           const SkIPoint& dstPoint);
+
+    void destroyResources(GrVkGpu* gpu);
+    void abandonResources();
+
+private:
+    bool createCopyProgram(GrVkGpu* gpu);
+
+    // Everything below is only created once and shared by all copy draws/pipelines
+    VkShaderModule fVertShaderModule;
+    VkShaderModule fFragShaderModule;
+    VkPipelineShaderStageCreateInfo fShaderStageInfo[2];
+
+    GrVkDescriptorSetManager::Handle fSamplerDSHandle;
+    VkPipelineLayout fPipelineLayout;
+
+    SkAutoTUnref<GrVkVertexBuffer> fVertexBuffer;
+    GrVkUniformBuffer*             fUniformBuffer;
+};
+
+#endif