Add Class/MemberDefinition to handle synthesized classes/members

tests/compiler/dart2js/closure/closure_test.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 'dart:io';
 import 'package:async_helper/async_helper.dart';
 import 'package:compiler/src/closure.dart';
 import 'package:compiler/src/common.dart';
 import 'package:compiler/src/compiler.dart';
 import 'package:compiler/src/diagnostics/diagnostic_listener.dart';
@@ skipping 36 matching lines @@
 /// Compute closure data mapping for [member] as a kernel based element.
 ///
 /// Fills [actualMap] with the data and [sourceSpanMap] with the source spans
 /// for the data origin.
 void computeKernelClosureData(Compiler compiler, MemberEntity member,
     Map<Id, String> actualMap, Map<Id, SourceSpan> sourceSpanMap) {
   KernelBackendStrategy backendStrategy = compiler.backendStrategy;
   KernelToElementMapForBuilding elementMap = backendStrategy.elementMap;
   GlobalLocalsMap localsMap = backendStrategy.globalLocalsMapForTesting;
   ClosureDataLookup closureDataLookup = backendStrategy.closureDataLookup;
+  MemberDefinition definition = elementMap.getMemberDefinition(member);
+  assert(definition.kind == MemberKind.regular,
+      failedAt(member, "Unexpected member definition $definition"));
   new ClosureIrChecker(actualMap, sourceSpanMap, elementMap, member,
           localsMap.getLocalsMap(member), closureDataLookup)
-      .run(elementMap.getMemberNode(member));
+      .run(definition.node);
 }
 
 /// Ast visitor for computing closure data.
 class ClosureAstComputer extends AbstractResolvedAstComputer {
   final ClosureDataLookup<ast.Node> closureDataLookup;
   final ClosureRepresentationInfo info;
 
   ClosureAstComputer(
       DiagnosticReporter reporter,
       Map<Id, String> actualMap,
@@ skipping 58 matching lines @@
 
 /// Compute a string representation of the data stored for [local] in [info].
 String computeLocalValue(ScopeInfo info, Local local) {
   StringBuffer sb = new StringBuffer();
   if (info.localIsUsedInTryOrSync(local)) {
     sb.write('inTry');
   }
   // TODO(johnniwinther,efortuna): Add more info (captured, boxed etc.).
   return sb.toString();
 }