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

client/dom/generated/src/frog/Int16Array.dart

Index: client/dom/generated/src/frog/Int16Array.dart
diff --git a/client/dom/generated/src/frog/Int16Array.dart b/client/dom/generated/src/frog/Int16Array.dart
index 0839f54c7fa1436e59f36f695f2b9e7a0c995df3..f503e55b7f438d19d367c6d6ec63812267e866ca 100644
--- a/client/dom/generated/src/frog/Int16Array.dart
+++ b/client/dom/generated/src/frog/Int16Array.dart
@@ -1,5 +1,5 @@
 
-class Int16ArrayJs extends ArrayBufferViewJs implements Int16Array, List<int> native "*Int16Array" {
+class _Int16ArrayJs extends _ArrayBufferViewJs implements Int16Array, List<int> native "*Int16Array" {
 
   factory Int16Array(int length) =>  _construct_Int16Array(length);
 
@@ -86,5 +86,5 @@ class Int16ArrayJs extends ArrayBufferViewJs implements Int16Array, List<int> na
 
   void setElements(Object array, [int offset = null]) native;
 
-  Int16ArrayJs subarray(int start, [int end = null]) native;
+  _Int16ArrayJs subarray(int start, [int end = null]) native;
 }