Make sure [this] is available for super sends.

dart/lib/compiler/implementation/ssa/closure.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.
 
 class ClosureFieldElement extends Element {
   ClosureFieldElement(SourceString name, ClassElement enclosing)
       : super(name, ElementKind.FIELD, enclosing);
 
   bool isInstanceMember() => true;
   bool isAssignable() => false;
@@ skipping 237 matching lines @@
     node.visitChildren(this);
   }
 
   visitSend(Send node) {
     Element element = elements[node];
     if (Elements.isLocal(element)) {
       useLocal(element);
     } else if (node.receiver === null &&
                Elements.isInstanceSend(node, elements)) {
       useLocal(closureData.thisElement);
+    } else if (node.isSuperCall) {
+      useLocal(closureData.thisElement);
     }
     node.visitChildren(this);
   }
 
   // If variables that are declared in the [node] scope are captured and need
   // to be boxed create a box-element and update the [capturingScopes] in the
   // current [closureData].
   // The boxed variables are updated in the [capturedVariableMapping].
   void attachCapturedScopeVariables(Node node) {
     Element box = null;
@@ skipping 164 matching lines @@
     declareLocal(elements[node]);
   }
 
   visitTryStatement(TryStatement node) {
     // TODO(ngeoffray): implement finer grain state.
     inTryCatchOrFinally = true;
     node.visitChildren(this);
     inTryCatchOrFinally = false;
   }
 }