Remove package imports from itself.

pkg/front_end/lib/src/fasta/bin/compile_platform.dart

 // Copyright (c) 2016, 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 'package:front_end/src/fasta/compile_platform.dart' as compile_platform;
+import '../compile_platform.dart' as compile_platform;
 
 const int iterations = const int.fromEnvironment("iterations", defaultValue: 1);
 
 main(List<String> arguments) async {
   for (int i = 0; i < iterations; i++) {
     if (i > 0) {
       print("\n");
     }
     await compile_platform.main(arguments);
   }
 }