Apply several phases only to entrypoint files (which currently are identified as

pkg/polymer/lib/src/transform/script_compactor.dart

Index: pkg/polymer/lib/src/transform/script_compactor.dart
diff --git a/pkg/polymer/lib/src/transform/script_compactor.dart b/pkg/polymer/lib/src/transform/script_compactor.dart
index 8a217e6f722154b1e539292243261baa03ec2636..2fcb1c6f8861fb356100dda99cd0cdaba55daa81 100644
--- a/pkg/polymer/lib/src/transform/script_compactor.dart
+++ b/pkg/polymer/lib/src/transform/script_compactor.dart
@@ -28,8 +28,8 @@ import 'common.dart';
  * elements annotated with `@CustomTag`.
  */
 class ScriptCompactor extends Transformer {
-  /** Only run this transformer on .html files. */
-  final String allowedExtensions = ".html";
+  /** Only run on entrypoint .html files under web or test. */
+  Future<bool> isPrimary(Asset input) => isHtmlInWebOrTest(input.id);
 
   Future apply(Transform transform) {
     var id = transform.primaryInput.id;