Make dart:dom implementation types private so they don't muddle the docs.

client/dom/generated/src/frog/Console.dart

Index: client/dom/generated/src/frog/Console.dart
diff --git a/client/dom/generated/src/frog/Console.dart b/client/dom/generated/src/frog/Console.dart
index b3e654229dd0789698c45bf55bec51c708c8c338..a197d134579b7346f5b71e4718ada305cd7b0dd9 100644
--- a/client/dom/generated/src/frog/Console.dart
+++ b/client/dom/generated/src/frog/Console.dart
@@ -2,14 +2,14 @@
 // 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 ConsoleJs
+class _ConsoleJs
     // Implement DOMType directly.  Console is sometimes a singleton
     // bag-of-properties without a prototype, so it can't inherit from
     // DOMTypeJs.
     implements Console, DOMType
     native "=(typeof console == 'undefined' ? {} : console)" {
 
-  MemoryInfoJs get memory() native "return this.memory;";
+  _MemoryInfoJs get memory() native "return this.memory;";
 
   List get profiles() native "return this.profiles;";