Add unified delay

common/urltest/context.go

@@ -0,0 +1,13 @@
+package urltest
+
+import "context"
+
+type contextKeyIsUnifiedDelay struct{}
+
+func ContextWithIsUnifiedDelay(ctx context.Context) context.Context {
+	return context.WithValue(ctx, contextKeyIsUnifiedDelay{}, true)
+}
+
+func IsUnifiedDelayFromContext(ctx context.Context) bool {
+	return ctx.Value(contextKeyIsUnifiedDelay{}) != nil
+}