Remove suppression for fixed Tint issue

Bug: tint:449
Change-Id: I7a1ee41bbd149c211096d0ce84c35ab8a0f937f9
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/63745
Commit-Queue: Austin Eng <enga@chromium.org>
Auto-Submit: Corentin Wallez <cwallez@chromium.org>
Reviewed-by: Brandon Jones <bajones@google.com>
Reviewed-by: Austin Eng <enga@chromium.org>
diff --git a/src/tests/unittests/validation/StorageTextureValidationTests.cpp b/src/tests/unittests/validation/StorageTextureValidationTests.cpp
index 3a671a2..0cfa3af 100644
--- a/src/tests/unittests/validation/StorageTextureValidationTests.cpp
+++ b/src/tests/unittests/validation/StorageTextureValidationTests.cpp
@@ -166,11 +166,13 @@
     }
 
     // Write-only storage textures cannot be declared in a vertex shader.
-    if ((false) /* TODO(https://crbug.com/tint/449) */) {
+    {
         wgpu::ShaderModule vsModule = utils::CreateShaderModule(device, R"(
             [[group(0), binding(0)]] var image0 : texture_storage_2d<rgba8unorm, write>;
-            [[stage(vertex)]] fn main([[builtin(vertex_index)]] vertex_index : u32) {
+            [[stage(vertex)]]
+            fn main([[builtin(vertex_index)]] vertex_index : u32) -> [[builtin(position)]] vec4<f32> {
                 textureStore(image0, vec2<i32>(i32(vertex_index), 0), vec4<f32>(1.0, 0.0, 0.0, 1.0));
+                return vec4<f32>(0.0);
             })");
 
         utils::ComboRenderPipelineDescriptor descriptor;