Add some copy support for vulkan msaa

src/gpu/vk/GrVkTextureRenderTarget.cpp

Index: src/gpu/vk/GrVkTextureRenderTarget.cpp
diff --git a/src/gpu/vk/GrVkTextureRenderTarget.cpp b/src/gpu/vk/GrVkTextureRenderTarget.cpp
index 532d0a256326b6b8b01aeac919f45e36772efd95..37b68af8276125f4fa537725f1abf648914cdaf5 100644
--- a/src/gpu/vk/GrVkTextureRenderTarget.cpp
+++ b/src/gpu/vk/GrVkTextureRenderTarget.cpp
@@ -49,7 +49,9 @@ GrVkTextureRenderTarget* GrVkTextureRenderTarget::Create(GrVkGpu* gpu,
         msImageDesc.fLevels = 1;
         msImageDesc.fSamples = desc.fSampleCnt;
         msImageDesc.fImageTiling = VK_IMAGE_TILING_OPTIMAL;
-        msImageDesc.fUsageFlags = VK_IMAGE_USAGE_COLOR_ATTACHMENT_BIT;
+        msImageDesc.fUsageFlags = VK_IMAGE_USAGE_COLOR_ATTACHMENT_BIT |
+                                  VK_IMAGE_USAGE_TRANSFER_DST_BIT |
+                                  VK_IMAGE_USAGE_TRANSFER_SRC_BIT;
         msImageDesc.fMemProps = VK_MEMORY_PROPERTY_DEVICE_LOCAL_BIT;
 
         if (!GrVkImage::InitImageInfo(gpu, msImageDesc, &msInfo)) {