s/OutputAttachment/RenderAttachment/g

But also keep OutputAttachment so it can be gradually changed in all
dependants.

See https://github.com/gpuweb/gpuweb/pull/1168 and
https://github.com/gpuweb/gpuweb/pull/1168

Bug: dawn:22
Change-Id: I6a1ec1de6c22ca4deac88b7fffde4b98d9d54a84
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/31040
Reviewed-by: Austin Eng <enga@chromium.org>
Reviewed-by: Stephen White <senorblanco@chromium.org>
Commit-Queue: Corentin Wallez <cwallez@chromium.org>
diff --git a/examples/ComputeBoids.cpp b/examples/ComputeBoids.cpp
index f958ab4..08487da 100644
--- a/examples/ComputeBoids.cpp
+++ b/examples/ComputeBoids.cpp
@@ -292,7 +292,7 @@
 
     queue = device.GetDefaultQueue();
     swapchain = GetSwapChain(device);
-    swapchain.Configure(GetPreferredSwapChainTextureFormat(), wgpu::TextureUsage::OutputAttachment,
+    swapchain.Configure(GetPreferredSwapChainTextureFormat(), wgpu::TextureUsage::RenderAttachment,
                         640, 480);
 
     initBuffers();