Fix Java style

PiperOrigin-RevId: 155087895
diff --git a/src/test/java/com/google/devtools/build/lib/syntax/SkylarkEvaluationTest.java b/src/test/java/com/google/devtools/build/lib/syntax/SkylarkEvaluationTest.java
index a71f656..353c573 100644
--- a/src/test/java/com/google/devtools/build/lib/syntax/SkylarkEvaluationTest.java
+++ b/src/test/java/com/google/devtools/build/lib/syntax/SkylarkEvaluationTest.java
@@ -216,8 +216,8 @@
       switch (name) {
         case "field": return "a";
         case "nset": return NestedSetBuilder.stableOrder().build();
+        default: return null;
       }
-      return null;
     }
 
     @Override