Remove EventListener attributes from Dart DOM API.

lib/dom/idl/dart/webkit-supplemental.idl

Index: lib/dom/idl/dart/webkit-supplemental.idl
diff --git a/lib/dom/idl/dart/webkit-supplemental.idl b/lib/dom/idl/dart/webkit-supplemental.idl
deleted file mode 100644
index 1bc37ee95ee9c4ed7afff4a79ed0db182aa6c7e4..0000000000000000000000000000000000000000
--- a/lib/dom/idl/dart/webkit-supplemental.idl
+++ /dev/null
@@ -1,20 +0,0 @@
-/**
- */
-
-// Supplements and corrects errors in WebKit IDL to better align with browser
-// neutral APIs.
-
-module default {
-  Node implements events::EventTarget;
-  MessagePort implements events::EventTarget;
-  EventSource implements events::EventTarget;
-  Window implements events::EventTarget;
-  ApplicationCache implements events::EventTarget;
-  XMLHttpRequest implements events::EventTarget;
-  XMLHttpRequestUpload implements events::EventTarget;
-  Notification implements events::EventTarget;
-  AbstractWorker implements events::EventTarget;
-  WorkerContext implements events::EventTarget;
-  SVGElementInstance implements events::EventTarget;
-  WebSocket implements events::EventTarget;
-}