Remove some dead code in TextureVk.

Found via the code coverage reports.

Bug: None
Change-Id: I3cd5911a627932cfde1bafd8353eef28993bbd42
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/122120
Kokoro: Kokoro <noreply+kokoro@google.com>
Reviewed-by: Austin Eng <enga@chromium.org>
Commit-Queue: Corentin Wallez <cwallez@chromium.org>
diff --git a/src/dawn/native/vulkan/TextureVk.cpp b/src/dawn/native/vulkan/TextureVk.cpp
index 2f4ccbd..68e858c 100644
--- a/src/dawn/native/vulkan/TextureVk.cpp
+++ b/src/dawn/native/vulkan/TextureVk.cpp
@@ -495,9 +495,10 @@
             flags |= VK_IMAGE_USAGE_COLOR_ATTACHMENT_BIT;
         }
     }
-    if (usage & kReadOnlyRenderAttachment) {
-        flags |= VK_IMAGE_USAGE_DEPTH_STENCIL_ATTACHMENT_BIT;
-    }
+
+    // Choosing Vulkan image usages should not know about kReadOnlyRenderAttachment because that's
+    // a property of when the image is used, not of the creation.
+    ASSERT(!(usage & kReadOnlyRenderAttachment));
 
     return flags;
 }