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

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

Index: client/dom/generated/src/frog/StyleSheetList.dart
diff --git a/client/dom/generated/src/frog/StyleSheetList.dart b/client/dom/generated/src/frog/StyleSheetList.dart
index fa4e86da110d71f4ab630f0b72f56915bf99e8f3..6fb9bf1adef0ceeb1ae23a0b691653b0905efffe 100644
--- a/client/dom/generated/src/frog/StyleSheetList.dart
+++ b/client/dom/generated/src/frog/StyleSheetList.dart
@@ -1,11 +1,11 @@
 
-class StyleSheetListJs extends DOMTypeJs implements StyleSheetList native "*StyleSheetList" {
+class _StyleSheetListJs extends _DOMTypeJs implements StyleSheetList native "*StyleSheetList" {
 
   int get length() native "return this.length;";
 
-  StyleSheetJs operator[](int index) native "return this[index];";
+  _StyleSheetJs operator[](int index) native "return this[index];";
 
-  void operator[]=(int index, StyleSheetJs value) {
+  void operator[]=(int index, _StyleSheetJs value) {
     throw new UnsupportedOperationException("Cannot assign element of immutable List.");
   }
   // -- start List<StyleSheet> mixins.
@@ -76,5 +76,5 @@ class StyleSheetListJs extends DOMTypeJs implements StyleSheetList native "*Styl
 
   // -- end List<StyleSheet> mixins.
 
-  StyleSheetJs item(int index) native;
+  _StyleSheetJs item(int index) native;
 }