Make DOMType the root of DOM implementation types.

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

 
-class HTMLCollectionJS implements HTMLCollection native "*HTMLCollection" {
+class HTMLCollectionJs extends DOMTypeJs implements HTMLCollection native "*HTMLCollection" {
 
   int get length() native "return this.length;";
 
-  NodeJS operator[](int index) native;
+  NodeJs operator[](int index) native;
 
-  void operator[]=(int index, NodeJS value) {
+  void operator[]=(int index, NodeJs value) {
     throw new UnsupportedOperationException("Cannot assign element of immutable List.");
   }
 
-  NodeJS item(int index) native;
+  NodeJs item(int index) native;
 
-  NodeJS namedItem(String name) native;
-
-  var dartObjectLocalStorage;
-
-  String get typeName() native;
+  NodeJs namedItem(String name) native;
 }