Support --use-kernel in memory_compiler

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

 // Copyright (c) 2012, 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 js_backend.backend;
 
 import '../common.dart';
 import '../common/backend_api.dart'
     show ForeignResolver, NativeRegistry, ImpactTransformer;
 import '../common/codegen.dart' show CodegenWorkItem;
@@ skipping 893 matching lines @@
   native.NativeResolutionEnqueuer get nativeResolutionEnqueuerForTesting =>
       _nativeResolutionEnqueuer;
 
   native.NativeEnqueuer get nativeCodegenEnqueuer => _nativeCodegenEnqueuer;
 
   /**
    * Unit test hook that returns code of an element as a String.
    *
    * Invariant: [element] must be a declaration element.
    */
-  String getGeneratedCode(Element element) {
-    assert(element.isDeclaration, failedAt(element));
+  String getGeneratedCode(MemberEntity element) {
+    assert(!(element is MemberElement && !element.isDeclaration),
+        failedAt(element));
     return jsAst.prettyPrint(generatedCode[element], compiler.options);
   }
 
   /// Generates the output and returns the total size of the generated code.
   int assembleProgram(ClosedWorld closedWorld) {
     int programSize = emitter.assembleProgram(namer, closedWorld);
     noSuchMethodRegistry.emitDiagnostic(reporter);
     int totalMethodCount = generatedCode.length;
     // TODO(redemption): Support `preMirrorsMethodCount` for entities.
     if (mirrorsCodegenAnalysis.preMirrorsMethodCount != null &&
@@ skipping 429 matching lines @@
 
   bool canUseAliasedSuperMember(MemberEntity member, Selector selector) {
     return !selector.isGetter;
   }
 
   /// Returns `true` if [member] is called from a subclass via `super`.
   bool isAliasedSuperMember(MemberEntity member) {
     return _aliasedSuperMembers.contains(member);
   }
 }