implemented copy surface as draw for metal gpu backend

Bug: skia:
Change-Id: Ie61bd6ad9f288b8a025d44f887a0954101a7d710
Reviewed-on: https://skia-review.googlesource.com/142687
Commit-Queue: Timothy Liang <timliang@google.com>
Reviewed-by: Greg Daniel <egdaniel@google.com>
diff --git a/gn/gpu.gni b/gn/gpu.gni
index 51a0dc2..ca86484 100644
--- a/gn/gpu.gni
+++ b/gn/gpu.gni
@@ -626,15 +626,21 @@
   "$_include/gpu/mtl/GrMtlTypes.h",
   "$_src/gpu/mtl/GrMtlCaps.h",
   "$_src/gpu/mtl/GrMtlCaps.mm",
+  "$_src/gpu/mtl/GrMtlCopyManager.h",
+  "$_src/gpu/mtl/GrMtlCopyManager.mm",
+  "$_src/gpu/mtl/GrMtlCopyPipelineState.h",
+  "$_src/gpu/mtl/GrMtlCopyPipelineState.mm",
   "$_src/gpu/mtl/GrMtlGpu.h",
   "$_src/gpu/mtl/GrMtlGpu.mm",
   "$_src/gpu/mtl/GrMtlGpuCommandBuffer.h",
-  "$_src/gpu/mtl/GrMtlRenderTarget.mm",
   "$_src/gpu/mtl/GrMtlRenderTarget.h",
-  "$_src/gpu/mtl/GrMtlTexture.mm",
+  "$_src/gpu/mtl/GrMtlRenderTarget.mm",
+  "$_src/gpu/mtl/GrMtlResourceProvider.h",
+  "$_src/gpu/mtl/GrMtlResourceProvider.mm",
   "$_src/gpu/mtl/GrMtlTexture.h",
-  "$_src/gpu/mtl/GrMtlTextureRenderTarget.mm",
+  "$_src/gpu/mtl/GrMtlTexture.mm",
   "$_src/gpu/mtl/GrMtlTextureRenderTarget.h",
+  "$_src/gpu/mtl/GrMtlTextureRenderTarget.mm",
   "$_src/gpu/mtl/GrMtlTrampoline.h",
   "$_src/gpu/mtl/GrMtlTrampoline.mm",
   "$_src/gpu/mtl/GrMtlUtil.h",