dart2js cps: Add path-sensitive types by inserting refinement IR nodes.

pkg/compiler/lib/src/common/names.dart

 // Copyright (c) 2015, 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 containing identifier, names, and selectors commonly used through
 /// the compiler.
 library dart2js.common.names;
 
 import '../elements/elements.dart' show
     Name,
@@ skipping 69 matching lines @@
 
   /// The selector for calling the to-string method on 'Object'.
   static final Selector toString_ =
       new Selector.call(Names.toString_, CallStructure.NO_ARGS);
 
   static final Selector hashCode_ =
       new Selector.getter(const PublicName('hashCode'));
 
   static final Selector compareTo =
       new Selector.call(const PublicName("compareTo"), CallStructure.ONE_ARG);
+
+  static final Selector equals = new Selector.binaryOperator('==');
 }
 
 /// [Uri]s commonly used.
 class Uris {
   /// The URI for 'dart:async'.
   static final Uri dart_async = new Uri(scheme: 'dart', path: 'async');
 
   /// The URI for 'dart:core'.
   static final Uri dart_core = new Uri(scheme: 'dart', path: 'core');
 
   /// The URI for 'dart:html'.
   static final Uri dart_html = new Uri(scheme: 'dart', path: 'html');
 
   /// The URI for 'dart:mirrors'.
   static final Uri dart_mirrors = new Uri(scheme: 'dart', path: 'mirrors');
 
   /// The URI for 'dart:_internal'.
   static final Uri dart__internal = new Uri(scheme: 'dart', path: '_internal');
 
   /// The URI for 'dart:_native_typed_data'.
   static final Uri dart__native_typed_data =
       new Uri(scheme: 'dart', path: '_native_typed_data');
 }