run-cts: Hint to use --isolate on POST failures.

Bug: dawn:1123
Change-Id: Ifac813410b7ec36e48282875c5915a5d8cf89282
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/75904
Commit-Queue: Corentin Wallez <cwallez@chromium.org>
Auto-Submit: Corentin Wallez <cwallez@chromium.org>
Reviewed-by: Ben Clayton <bclayton@google.com>
Commit-Queue: Ben Clayton <bclayton@google.com>
diff --git a/src/dawn_node/tools/src/cmd/run-cts/main.go b/src/dawn_node/tools/src/cmd/run-cts/main.go
index f60e024..98ae279 100644
--- a/src/dawn_node/tools/src/cmd/run-cts/main.go
+++ b/src/dawn_node/tools/src/cmd/run-cts/main.go
@@ -555,7 +555,7 @@
 		}
 		postResp, err := http.Post(fmt.Sprintf("http://localhost:%v/run?%v", port, r.testcases[idx]), "", &bytes.Buffer{})
 		if err != nil {
-			res.error = fmt.Errorf("server POST failure. Restarting server...")
+			res.error = fmt.Errorf("server POST failure. Restarting server... This can happen when there is a crash. Try running with --isolate.")
 			res.status = fail
 			results <- res
 			stopServer()