Vulkan: Shader path for framebuffer-to-texture copy

Part 1 in a series of changes to perform image copies on the GPU.

Bug: angleproject:2958
Change-Id: I6264a880865c4738c0866f2dc71af63425fc4118
Reviewed-on: https://chromium-review.googlesource.com/c/1370724
Commit-Queue: Shahbaz Youssefi <syoussefi@chromium.org>
Reviewed-by: Jamie Madill <jmadill@chromium.org>
diff --git a/src/libANGLE/renderer/vulkan/RenderTargetVk.cpp b/src/libANGLE/renderer/vulkan/RenderTargetVk.cpp
index b78b9e0..e2ca46f 100644
--- a/src/libANGLE/renderer/vulkan/RenderTargetVk.cpp
+++ b/src/libANGLE/renderer/vulkan/RenderTargetVk.cpp
@@ -67,18 +67,29 @@
     mImage->addWriteDependency(framebufferVk);
 }
 
+vk::ImageHelper &RenderTargetVk::getImage()
+{
+    ASSERT(mImage && mImage->valid());
+    return *mImage;
+}
+
 const vk::ImageHelper &RenderTargetVk::getImage() const
 {
     ASSERT(mImage && mImage->valid());
     return *mImage;
 }
 
-vk::ImageView *RenderTargetVk::getImageView() const
+vk::ImageView *RenderTargetVk::getDrawImageView() const
 {
     ASSERT(mImageView && mImageView->valid());
     return mImageView;
 }
 
+vk::ImageView *RenderTargetVk::getReadImageView() const
+{
+    return getDrawImageView();
+}
+
 const vk::Format &RenderTargetVk::getImageFormat() const
 {
     ASSERT(mImage && mImage->valid());