Introduce LibraryEntity

pkg/compiler/lib/src/serialization/equivalence.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.
 
 /// Functions for asserting equivalence across serialization.
 
 library dart2js.serialization.equivalence;
 
 import '../closure.dart';
 import '../common/resolution.dart';
@@ skipping 133 matching lines @@
 bool areSelectorsEquivalent(Selector a, Selector b) {
   if (identical(a, b)) return true;
   if (a == null || b == null) return false;
   return a.kind == b.kind &&
       a.callStructure == b.callStructure &&
       areNamesEquivalent(a.memberName, b.memberName);
 }
 
 /// Returns `true` if the names [a] and [b] are equivalent.
 bool areNamesEquivalent(Name a, Name b) {
+  LibraryElement library1 = a.library;
+  LibraryElement library2 = b.library;
   return a.text == b.text &&
       a.isSetter == b.isSetter &&
-      areElementsEquivalent(a.library, b.library);
+      areElementsEquivalent(library1, library2);
 }
 
 /// Returns `true` if the dynamic uses [a] and [b] are equivalent.
 bool areDynamicUsesEquivalent(DynamicUse a, DynamicUse b) {
   return areSelectorsEquivalent(a.selector, b.selector);
 }
 
 /// Returns `true` if the static uses [a] and [b] are equivalent.
 bool areStaticUsesEquivalent(StaticUse a, StaticUse b) {
   return a.kind == b.kind && areElementsEquivalent(a.element, b.element);
@@ skipping 1876 matching lines @@
 }
 
 bool areMetadataAnnotationsEquivalent(
     MetadataAnnotation metadata1, MetadataAnnotation metadata2) {
   if (metadata1 == metadata2) return true;
   if (metadata1 == null || metadata2 == null) return false;
   return areElementsEquivalent(
           metadata1.annotatedElement, metadata2.annotatedElement) &&
       areConstantsEquivalent(metadata1.constant, metadata2.constant);
 }