wgsl: Make colon optional for case statements

Fixed: tint:1485
Change-Id: I76af5a284cb455170bed27e852a4bab47c5dc491
Reviewed-on: https://dawn-review.googlesource.com/c/tint/+/85525
Reviewed-by: Ben Clayton <bclayton@google.com>
Kokoro: Kokoro <noreply+kokoro@google.com>
diff --git a/docs/tint/origin-trial-changes.md b/docs/tint/origin-trial-changes.md
index 3bb1e4e..3f3c61d 100644
--- a/docs/tint/origin-trial-changes.md
+++ b/docs/tint/origin-trial-changes.md
@@ -6,6 +6,7 @@
 
 * Parentheses are no longer required around expressions for if and switch statements [tint:1424](crbug.com/tint/1424)
 * Compound assignment statements are now supported. [tint:1325](https://crbug.com/tint/1325)
+* The colon in case statements is now optional. [tint:1485](crbug.com/tint/1485)
 
 ### Breaking changes