Code cleanup: moving compiler perf tests to compiler/tool

pkg/compiler/tool/dart2js_profile_many.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.profile_many;
 
 import 'dart:async';
 
-import 'dart2js.dart' as cmdline;
+import 'package:compiler/src/dart2js.dart' as cmdline
 
 const String USAGE = """
 Usage: dart2js_profile_many.dart [OPTIONS] [FILES]
 
 Invokes dart2js separately for each file using the given options.
 This is for profiling multiple compilations in the Dart Observatory.
 """;
 
 printUsage() {
   print(USAGE);
@@ skipping 22 matching lines @@
 
   Future.forEach(files, (String file) {
     List subargs = [];
     subargs.addAll(options);
     subargs.add(file);
     return cmdline.compilerMain(subargs).catchError((e) {});
   }).then((_) {
     print("Done");
   });
 }