Add GrVkCopyPipeline to handle vulkan copies as draws

src/gpu/vk/GrVkResourceProvider.h

Index: src/gpu/vk/GrVkResourceProvider.h
diff --git a/src/gpu/vk/GrVkResourceProvider.h b/src/gpu/vk/GrVkResourceProvider.h
index 19d493af92bf9772c70d9c6a908d27a6a5ffb6ad..b9e98e72ccd45c15ac2ff4ad93e4649a08a9e591 100644
--- a/src/gpu/vk/GrVkResourceProvider.h
+++ b/src/gpu/vk/GrVkResourceProvider.h
@@ -26,6 +26,7 @@
 class GrPipeline;
 class GrPrimitiveProcessor;
 class GrTextureParams;
+class GrVkCopyPipeline;
 class GrVkGpu;
 class GrVkPipeline;
 class GrVkPrimaryCommandBuffer;
@@ -50,6 +51,10 @@ public:
                                  const GrVkRenderPass& renderPass,
                                  VkPipelineLayout layout);
 
+    GrVkCopyPipeline* findOrCreateCopyPipeline(const GrVkRenderTarget* dst,
+                                               VkPipelineShaderStageCreateInfo*,
+                                               VkPipelineLayout);
+
     GR_DEFINE_RESOURCE_HANDLE_CLASS(CompatibleRPHandle);
 
     // Finds or creates a simple render pass that matches the target, increments the refcount,
@@ -224,6 +229,9 @@ private:
     // Central cache for creating pipelines
     VkPipelineCache fPipelineCache;
 
+    // Cache of previously created copy pipelines
+    SkTArray<GrVkCopyPipeline*> fCopyPipelines;
+
     SkSTArray<4, CompatibleRenderPassSet> fRenderPassArray;
 
     // Array of PrimaryCommandBuffers that are currently in flight