Refactor CompilerOutput

tests/compiler/dart2js/source_map_test.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.
 
 // Test that options '--source-map' and '--out' correctly adds
 // `sourceMappingURL` and "file" attributes to source file and source map file.
 
 library test.source_map;
 
 import 'package:async_helper/async_helper.dart';
+import 'package:compiler/compiler_new.dart';
 import 'package:expect/expect.dart';
 import 'memory_compiler.dart';
 
 const SOURCE = const {
   '/main.dart': """
 main() {}
 """,
 };
 
 void find(String text, String substring, bool expected) {
@@ skipping 19 matching lines @@
   if (sourceMap != null) {
     options.add("--source-map=$sourceMap");
   }
 
   await runCompiler(
       entryPoint: Uri.parse('memory:/main.dart'),
       memorySourceFiles: SOURCE,
       showDiagnostics: true,
       outputProvider: collector,
       options: options);
-  String jsOutput = collector.getOutput('', 'js');
+  String jsOutput = collector.getOutput('', OutputType.js);
   Expect.isNotNull(jsOutput);
   if (mapping != null) {
     find(jsOutput, '//# sourceMappingURL=$mapping', true);
   } else {
     find(jsOutput, '//# sourceMappingURL=', false);
   }
-  String jsSourceMapOutput = collector.getOutput('', 'js.map');
+  String jsSourceMapOutput = collector.getOutput('', OutputType.sourceMap);
   Expect.isNotNull(jsSourceMapOutput);
   if (file != null) {
     find(jsSourceMapOutput, '"file": "$file"', true);
   } else {
     find(jsSourceMapOutput, '"file": ', false);
   }
 }
 
 void main() {
   asyncTest(() async {
     await test();
     await test(sourceMap: 'file:/out.js.map');
     await test(out: 'file:/out.js');
     await test(
         out: 'file:/out.js',
         sourceMap: 'file:/out.js.map',
         file: 'out.js',
         mapping: 'out.js.map');
     await test(
         out: 'file:/dir/out.js',
         sourceMap: 'file:/dir/out.js.map',
         file: 'out.js',
         mapping: 'out.js.map');
   });
 }