Implement call operator.

lib/compiler/implementation/elements/elements.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('elements');
 
 #import('../tree/tree.dart');
 #import('../scanner/scannerlib.dart');
 #import('../leg.dart');  // TODO(karlklose): we only need type.
 #import('../util/util.dart');
@@ skipping 1132 matching lines @@
   }
 
   static bool isInstanceMethod(Element element) {
     return (element != null)
            && element.isInstanceMember()
            && (element.kind === ElementKind.FUNCTION);
   }
 
   static bool isInstanceSend(Send send, TreeElements elements) {
     Element element = elements[send];
-    if (element === null) return !isClosureSend(send, elements);
+    if (element === null) return !isClosureSend(send, element);
     return isInstanceMethod(element) || isInstanceField(element);
   }
 
-  static bool isClosureSend(Send send, TreeElements elements) {
+  static bool isClosureSend(Send send, Element element) {
     if (send.isPropertyAccess) return false;
     if (send.receiver !== null) return false;
-    Element element = elements[send];
     // (o)() or foo()().
     if (element === null && send.selector.asIdentifier() === null) return true;
     if (element === null) return false;
     // foo() with foo a local or a parameter.
     return isLocal(element);
   }
 
   static SourceString constructConstructorName(SourceString receiver,
                                                SourceString selector) {
     String r = receiver.slowToString();
@@ skipping 114 matching lines @@
   TypeVariableElement(name, Element enclosing, this.cachedNode,
                       [this.type, this.bound])
     : super(name, ElementKind.TYPE_VARIABLE, enclosing);
 
   TypeVariableType computeType(compiler) => type;
 
   Node parseNode(compiler) => cachedNode;
 
   String toString() => "${enclosingElement.toString()}.${name.slowToString()}";
 }