Use the entity model for dump_info.

pkg/compiler/lib/src/js_backend/mirrors_data.dart

 // Copyright (c) 2017, 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.
 
 import '../common.dart';
 import '../common_elements.dart';
 import '../compiler.dart';
 import '../constants/values.dart';
 import '../elements/elements.dart' show AbstractFieldElement, Element;
 import '../elements/entities.dart';
@@ skipping 112 matching lines @@
   bool retainMetadataOfTypedef(TypedefEntity element);
   bool retainMetadataOfClass(ClassEntity element);
   bool retainMetadataOfMember(MemberEntity element);
 
   /// Returns true if this element has to be enqueued due to
   /// mirror usage. Might be a subset of [referencedFromMirrorSystem] if
   /// normal tree shaking is still active ([isTreeShakingDisabled] is false).
   bool isLibraryRequiredByMirrorSystem(LibraryEntity element);
   bool isClassRequiredByMirrorSystem(ClassEntity element);
   bool isMemberRequiredByMirrorSystem(MemberEntity element);
+  bool isClassResolved(ClassEntity element);
 }
 
 abstract class MirrorsDataBuilder {
   void registerUsedMember(MemberEntity member);
 
   /// Called by [MirrorUsageAnalyzerTask] after it has merged all @MirrorsUsed
   /// annotations. The arguments corresponds to the unions of the corresponding
   /// fields of the annotations.
   void registerMirrorUsage(
       Set<String> symbols, Set<Element> targets, Set<Element> metaTargets);
@@ skipping 564 matching lines @@
   }
 
   /// Called when `const Symbol(name)` is seen.
   void registerConstSymbol(String name) {
     symbolsUsed.add(name);
     if (name.endsWith('=')) {
       symbolsUsed.add(name.substring(0, name.length - 1));
     }
   }
 }