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

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

Index: client/dom/generated/src/frog/IDBIndex.dart
diff --git a/client/dom/generated/src/frog/IDBIndex.dart b/client/dom/generated/src/frog/IDBIndex.dart
index 79e7b42e65ac86aa93630845099b346df595f4cf..c45968c9a844fb74d697c76f0a4a351e1de1514d 100644
--- a/client/dom/generated/src/frog/IDBIndex.dart
+++ b/client/dom/generated/src/frog/IDBIndex.dart
@@ -1,5 +1,5 @@
 
-class IDBIndexJs extends DOMTypeJs implements IDBIndex native "*IDBIndex" {
+class _IDBIndexJs extends _DOMTypeJs implements IDBIndex native "*IDBIndex" {
 
   String get keyPath() native "return this.keyPath;";
 
@@ -7,17 +7,17 @@ class IDBIndexJs extends DOMTypeJs implements IDBIndex native "*IDBIndex" {
 
   String get name() native "return this.name;";
 
-  IDBObjectStoreJs get objectStore() native "return this.objectStore;";
+  _IDBObjectStoreJs get objectStore() native "return this.objectStore;";
 
   bool get unique() native "return this.unique;";
 
-  IDBRequestJs count([IDBKeyRangeJs range = null]) native;
+  _IDBRequestJs count([_IDBKeyRangeJs range = null]) native;
 
-  IDBRequestJs getObject(IDBKeyJs key) native;
+  _IDBRequestJs getObject(_IDBKeyJs key) native;
 
-  IDBRequestJs getKey(IDBKeyJs key) native;
+  _IDBRequestJs getKey(_IDBKeyJs key) native;
 
-  IDBRequestJs openCursor([IDBKeyRangeJs range = null, int direction = null]) native;
+  _IDBRequestJs openCursor([_IDBKeyRangeJs range = null, int direction = null]) native;
 
-  IDBRequestJs openKeyCursor([IDBKeyRangeJs range = null, int direction = null]) native;
+  _IDBRequestJs openKeyCursor([_IDBKeyRangeJs range = null, int direction = null]) native;
 }