Move common identifiers, names and selectors to a separate library.

pkg/compiler/lib/src/js_emitter/full_emitter/emitter.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.js_emitter.full_emitter;
 
 import 'dart:convert';
 import 'dart:collection' show HashMap;
 
 import 'package:js_runtime/shared/embedded_names.dart' as embeddedNames;
@@ skipping 17 matching lines @@
 
 import '../../diagnostics/messages.dart' show MessageKind;
 
 import '../../diagnostics/spannable.dart' show
     NO_LOCATION_SPANNABLE;
 
 import '../../elements/elements.dart' show
     ConstructorBodyElement,
     ElementKind,
     FieldElement,
+    Name,
     ParameterElement,
     TypeVariableElement,
     MethodElement,
     MemberElement;
 
 import '../../hash/sha1.dart' show Hasher;
 
 import '../../io/code_output.dart';
 
 import '../../io/line_column_provider.dart' show
@@ skipping 2071 matching lines @@
     for (Element element in compiler.enqueuer.codegen.newlyEnqueuedElements) {
       if (element.isInstanceMember) {
         cachedClassBuilders.remove(element.enclosingClass);
 
         nativeEmitter.cachedBuilders.remove(element.enclosingClass);
 
       }
     }
   }
 }