Move dart2js from sdk/lib/_internal/compiler to pkg/compiler

tests/compiler/dart2js/message_kind_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.
 
 library dart2js.test.message_kind_helper;
 
 import 'package:expect/expect.dart';
 import 'dart:async';
 
-import 'package:compiler/implementation/dart2jslib.dart' show
+import 'package:compiler/src/dart2jslib.dart' show
     Compiler,
     MessageKind;
 
 import 'memory_compiler.dart';
 
 const String ESCAPE_REGEXP = r'[[\]{}()*+?.\\^$|]';
 
 /// Most examples generate a single diagnostic.
 /// Add an exception here if a single diagnostic cannot be produced.
 /// However, consider that a single concise diagnostic is easier to understand,
@@ skipping 117 matching lines @@
       Expect.isTrue(!pendingStuff || kindsWithPendingClasses.contains(kind));
 
       if (!pendingStuff && !compiler.compilerWasCancelled) {
         // If there is pending stuff, or the compiler was cancelled, we
         // shouldn't reuse the compiler.
         cachedCompiler = compiler;
       }
     });
   }).then((_) => cachedCompiler);
 }