[gold] Add CORS to tree status endpoint

Change-Id: I9a40484beb4cf3911727b1993af880b7d271fa56
Reviewed-on: https://skia-review.googlesource.com/c/buildbot/+/233466
Reviewed-by: Kevin Lubick <kjlubick@google.com>
Commit-Queue: Kevin Lubick <kjlubick@google.com>
diff --git a/golden/cmd/skiacorrectness/main.go b/golden/cmd/skiacorrectness/main.go
index 08f9b68..b160dd5 100644
--- a/golden/cmd/skiacorrectness/main.go
+++ b/golden/cmd/skiacorrectness/main.go
@@ -606,7 +606,7 @@
 	// set up the app router that might be authenticated and logs everything except for the status
 	// endpoint which is polled a lot.
 	appRouter := mux.NewRouter()
-	appRouter.HandleFunc("/json/trstatus", handlers.JsonStatusHandler)
+	appRouter.HandleFunc("/json/trstatus", httputils.CorsCredentialsHandler(handlers.JsonStatusHandler, ".skia.org"))
 	// Images should not be served gzipped, which can sometimes have issues
 	// when serving an image from a NetDiffstore with HTTP2. Additionally, is wasteful
 	// given PNGs typically have zlib compression anyway.