Use a symbol for static length/name (conflicts with Function properties in ES5: cannot redefine Fun…

lib/src/codegen/js_names.dart

 // Copyright (c) 2015, 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.
 
 import 'dart:collection';
 
 import '../js/js_ast.dart';
+import '../options.dart';
 
 /// Unique instance for temporary variables. Will be renamed consistently
 /// across the entire file. Different instances will be named differently
 /// even if they have the same name, this makes it safe to use in code
 /// generation without needing global knowledge. See [JSNamer].
 ///
 // TODO(jmesserly): move into js_ast? add a boolean to Identifier?
 class TemporaryId extends Identifier {
   TemporaryId(String name) : super(name);
 }
@@ skipping 258 matching lines @@
     case "private":
     case "protected":
     case "public":
     case "static":
     case "yield":
       return strictMode;
   }
   return false;
 }
 
-/// Returns true for invalid static field names in strict mode.
+/// Returns true for invalid static field names in strict mode or for some
+/// transpilers (e.g. when doing ES6->ES5 lowering with the Closure Compiler).
 /// In particular, "caller" "callee" and "arguments" cannot be used.
-bool invalidStaticFieldName(String name) {
+bool invalidStaticFieldName(String name, CodegenOptions options) {
   switch (name) {
     case "arguments":
     case "caller":
     case "callee":
       return true;
+    // Workarounds for Closure:
+    // (see https://github.com/google/closure-compiler/issues/1460)
+    case "name":
+    case "length":
+      return options.closure;
   }
   return false;
 }