Get rid of Dynamic.

lib/html/templates/html/impl/impl_EventTarget.darttemplate

Index: lib/html/templates/html/impl/impl_EventTarget.darttemplate
diff --git a/lib/html/templates/html/impl/impl_EventTarget.darttemplate b/lib/html/templates/html/impl/impl_EventTarget.darttemplate
index 94861d8756679cd776ea342c1afa3f438275e155..23e8f5b9dcfbd8ca068e89ab2aee85daf7ec49b5 100644
--- a/lib/html/templates/html/impl/impl_EventTarget.darttemplate
+++ b/lib/html/templates/html/impl/impl_EventTarget.darttemplate
@@ -6,7 +6,7 @@ class _EventsImpl implements Events {
   /* Raw event target. */
   // TODO(jacobr): it would be nice if we could specify this as
   // _EventTargetImpl or EventTarget
-  final Dynamic _ptr;
+  final _ptr;
 
   _EventsImpl(this._ptr);
 
@@ -18,7 +18,7 @@ class _EventsImpl implements Events {
 class _EventListenerListImpl implements EventListenerList {
 
   // TODO(jacobr): make this _EventTargetImpl
-  final Dynamic _ptr;
+  final _ptr;
   final String _type;
 
   _EventListenerListImpl(this._ptr, this._type);