Handle super accesses loaded from .dill

pkg/compiler/lib/src/kernel/element_map_impl.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.
 
 library dart2js.kernel.element_map;
 
 import 'package:kernel/ast.dart' as ir;
 import 'package:kernel/clone.dart';
 import 'package:kernel/type_algebra.dart';
 
@@ skipping 311 matching lines @@
               isStatic: isStatic,
               isExternal: isExternal,
               isAbstract: isAbstract);
           break;
       }
       _memberList.add(new _FunctionData(node, node.function));
       return function;
     });
   }
 
+  MemberEntity getSuperMember(ir.Member context, ir.Name name, ir.Member target,
+      {bool setter: false}) {
+    if (target != null) {
+      return getMember(target);
+    }
+    KClass cls = getMember(context).enclosingClass;
+    KClass superclass = _getSuperType(cls)?.element;
+    while (superclass != null) {
+      _KClassEnv env = _classEnvs[superclass.classIndex];
+      ir.Member superMember = env.lookupMember(name.name, setter: setter);
+      if (superMember != null) {
+        return getMember(superMember);
+      }
+      superclass = _getSuperType(superclass)?.element;
+    }
+    throw new SpannableAssertionFailure(
+        cls, "No super method member found for ${name} in $cls.");
+  }
+
   /// Returns the kernel [ir.Procedure] node for the [method].
   ir.Procedure _lookupProcedure(KFunction method) {
     return _memberList[method.memberIndex].node;
   }
 
   KField _getField(ir.Field node) {
     return _fieldMap.putIfAbsent(node, () {
       int memberIndex = _memberList.length;
       KLibrary library;
       KClass enclosingClass;
@@ skipping 1142 matching lines @@
     return node.isExternal &&
         !elementMap.isForeignLibrary(node.enclosingLibrary);
   }
 
   @override
   bool isJsInteropMember(MemberEntity element) {
     // TODO(johnniwinther): Compute this.
     return false;
   }
 }