Enforce LF line endings in the git database.

tests/compiler/dart2js/mirrors/mirrors_test_helper.dart

 // Copyright (c) 2013, 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.
 
 import 'dart:io';
 import 'dart:async';
 
 import 'package:compiler/src/mirrors/source_mirrors.dart';
 import 'package:compiler/src/mirrors/analyze.dart' as source_mirrors;
 import 'package:compiler/src/source_file_provider.dart';
@@ skipping 17 matching lines @@
       new Uri.file('${Platform.packageRoot}/'));
   var provider = new CompilerSourceFileProvider();
   var handler = new FormattingDiagnosticHandler(provider);
   return source_mirrors.analyze(
       [testUri],
       libraryRoot,
       packageRoot,
       provider,
       handler);
 }