Use default params when --destructure-named-params + fix renaming of reserved destructured params

lib/src/js/template.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.
 
 part of js_ast;
 
 class TemplateManager {
   Map<String, Template> expressionTemplates = new Map<String, Template>();
   Map<String, Template> statementTemplates = new Map<String, Template>();
 
@@ skipping 839 matching lines @@
   }
 
   @override
   Instantiator visitObjectBindingPattern(ObjectBindingPattern node) {
     List<Instantiator> makeVars = node.variables.map(this.visit).toList();
     return (arguments) {
       return new ObjectBindingPattern(
           makeVars.map((m) => m(arguments)).toList());
     };
   }
+
+  @override
+  Instantiator visitSimpleBindingPattern(SimpleBindingPattern node) =>
+      (arguments) => new SimpleBindingPattern(new Identifier(node.name.name));
 }
 
 /**
  * InterpolatedNodeAnalysis determines which AST trees contain
  * [InterpolatedNode]s, and the names of the named interpolated nodes.
  */
 class InterpolatedNodeAnalysis extends BaseVisitor {
   final Set<Node> containsInterpolatedNode = new Set<Node>();
   final Set<String> holeNames = new Set<String>();
   int count = 0;
@@ skipping 13 matching lines @@
     if (count != before) containsInterpolatedNode.add(node);
     return null;
   }
 
   visitInterpolatedNode(InterpolatedNode node) {
     containsInterpolatedNode.add(node);
     if (node.isNamed) holeNames.add(node.nameOrPosition);
     ++count;
   }
 }