Use serialized scope info to test incremental compiler.

dart/pkg/dart2js_incremental/lib/dart2js_incremental.dart

 // Copyright (c) 2014, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 library dart2js_incremental;
 
 import 'dart:async' show
     Future;
 
 import 'dart:profiler' show
@@ skipping 57 matching lines @@
       throw new ArgumentError('libraryRoot is null.');
     }
     if (inputProvider == null) {
       throw new ArgumentError('inputProvider is null.');
     }
     if (diagnosticHandler == null) {
       throw new ArgumentError('diagnosticHandler is null.');
     }
   }
 
+  LibraryElement get mainApp => _compiler.mainApp;
+
+  Compiler get compiler => _compiler;
+
   Future<bool> compile(Uri script) {
     return _reuseCompiler(null).then((Compiler compiler) {
       _compiler = compiler;
       return compiler.run(script);
     });
   }
 
   Future<Compiler> _reuseCompiler(
       Future<bool> reuseLibrary(LibraryElement library)) {
     List<String> options = this.options == null
@@ skipping 52 matching lines @@
   $dart_unsafe_eval.patch(#);
   return main(args);
 }""", updates);
 
 
     jsAst.Printer printer = new jsAst.Printer(_compiler, null);
     printer.blockOutWithoutBraces(mainRunner);
     return printer.outBuffer.getText();
   }
 }