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

pkg/compiler/lib/src/mirrors/dart2js_member_mirrors.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.
 
 part of dart2js.mirrors;
 
 //------------------------------------------------------------------------------
 // Member mirrors implementation.
 //------------------------------------------------------------------------------
 
@@ skipping 219 matching lines @@
                               bool isNamed)
       : super._normal(method, element, isOptional, isNamed);
 
   InitializingFormalElement get _fieldParameterElement => _element;
 
   bool get isInitializingFormal => true;
 
   VariableMirror get initializedField => new Dart2JsFieldMirror(
       owner.owner, _fieldParameterElement.fieldElement);
 }