dart2js cps: Handle optional parameters in builder.

pkg/analyzer2dart/lib/src/cps_generator.dart

 // Copyright (c) 2014, 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 analyzer2dart.cps_generator;
 
 import 'package:analyzer/analyzer.dart';
 
 import 'package:compiler/src/dart_types.dart' as dart2js;
 import 'package:compiler/src/elements/elements.dart' as dart2js;
@@ skipping 199 matching lines @@
 
   @override
   ir.Node visitLocalFunctionAccess(AstNode node, AccessSemantics semantics) {
     return handleLocalAccess(node, semantics);
   }
 
   ir.Primitive handleLocalInvocation(MethodInvocation node,
                                      AccessSemantics semantics) {
     analyzer.Element staticElement = semantics.element;
     dart2js.Element element = converter.convertElement(staticElement);
+    ir.Primitive receiver = irBuilder.buildLocalGet(element);
     List<ir.Definition> arguments = visitArguments(node.argumentList);
-    return irBuilder.buildLocalInvocation(
-      element,
+    return irBuilder.buildFunctionExpressionInvocation(
+      receiver,
       createSelectorFromMethodInvocation(
           node.argumentList, node.methodName.name),
       arguments);
   }
 
   @override
   ir.Node visitLocalVariableInvocation(MethodInvocation node,
                                        AccessSemantics semantics) {
     return handleLocalInvocation(node, semantics);
   }
@@ skipping 336 matching lines @@
     return irBuilder.buildTypeOperator(
         visit(node.expression),
         converter.convertType(node.type.type),
         isTypeTest: false);
   }
 }
 
 class NullCapturedVariableInfo extends DartCapturedVariableInfo {
   Iterable get capturedVariables => const [];
 }