Extract ResolutionWorldBuilderBase from ElementResolutionWorldBuilder

pkg/compiler/lib/src/elements/entities.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.
 
 library entities;
 
 import '../common.dart';
 
 /// Abstract interface for entities.
 ///
@@ skipping 23 matching lines @@
 /// and/or Dart-in-JS classes.
 abstract class ClassEntity extends Entity {
   /// If this is a normal class, the enclosing library for this class. If this
   /// is a closure class, the enclosing class of the closure for which it was
   /// created.
   LibraryEntity get library;
 
   /// Whether this is a synthesized class for a closurized method or local
   /// function.
   bool get isClosure;
+
+  /// Whether this is an abstract class.
+  bool get isAbstract;
 }
 
 abstract class TypeVariableEntity extends Entity {
   /// The class or generic method that declared this type variable.
   Entity get typeDeclaration;
 
   /// The index of this type variable in the type variables of its
   /// [typeDeclaration].
   int get index;
 }
@@ skipping 90 matching lines @@
   Entity get executableContext;
 
   /// The outermost member that contains this element.
   ///
   /// For top level, static or instance members, the member context is the
   /// element itself. For parameters, local variables and nested closures, the
   /// member context is the top level, static or instance member in which it is
   /// defined.
   MemberEntity get memberContext;
 }