Update unit tests

dart/pkg/compiler/lib/src/use_unused_api.dart

Index: dart/pkg/compiler/lib/src/use_unused_api.dart
diff --git a/dart/pkg/compiler/lib/src/use_unused_api.dart b/dart/pkg/compiler/lib/src/use_unused_api.dart
index 3577bbecbfa62e6b31e5ec9e1274871d5b619bcd..4a4c351a3ecf8f257ee0d070ebd9b3901169c336 100644
--- a/dart/pkg/compiler/lib/src/use_unused_api.dart
+++ b/dart/pkg/compiler/lib/src/use_unused_api.dart
@@ -63,6 +63,7 @@ void main(List<String> arguments) {
   useCompiler(null);
   useTypes();
   useCodeEmitterTask(null);
+  useScript(null);
 }
 
 useApi() {
@@ -270,3 +271,7 @@ useTypes() {
 useCodeEmitterTask(js_emitter.CodeEmitterTask codeEmitterTask) {
   codeEmitterTask.oldEmitter.clearCspPrecompiledNodes();
 }
+
+useScript(dart2jslib.Script script) {
+  script.copyWithFile(null);
+}