Remove now unused file.

lib/html/src/dart2js_IDBOpenDBRequestImplementation.dart

Index: lib/html/src/dart2js_IDBOpenDBRequestImplementation.dart
diff --git a/lib/html/src/dart2js_IDBOpenDBRequestImplementation.dart b/lib/html/src/dart2js_IDBOpenDBRequestImplementation.dart
deleted file mode 100644
index ddc308f433d5cfb715057ec5f6db1f169618c300..0000000000000000000000000000000000000000
--- a/lib/html/src/dart2js_IDBOpenDBRequestImplementation.dart
+++ /dev/null
@@ -1,27 +0,0 @@
-// Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
-// for details. All rights reserved. Use of this source code is governed by a
-// BSD-style license that can be found in the LICENSE file.
-
-// IDBOpenDBRequest.  IDBFactory.open returns a plain IDBRequest on Chrome and
-// Dartium but an IDBOpenDBRequest on Firefox.  Chrome/Dartium is expected to
-// change at some point as IDBOpenDBRequest is more standard.  When it appears
-// in the WebKit IDL we can remove this hand-written file.
-//
-// See:
-// http://www.w3.org/TR/IndexedDB/#request-api
-// http://dvcs.w3.org/hg/IndexedDB/raw-file/tip/Overview.html#request-api
-
-class _IDBOpenDBRequestImpl extends _IDBRequestImpl implements IDBOpenDBRequest
-    native "*IDBOpenDBRequest" {
-
-  _IDBOpenDBRequestEventsImpl get on() =>
-    new _IDBOpenDBRequestEventsImpl(this);
-}
-
-class _IDBOpenDBRequestEventsImpl extends _IDBRequestEventsImpl implements IDBOpenDBRequestEvents {
-  _IDBOpenDBRequestEventsImpl(_ptr) : super(_ptr);
-
-  EventListenerList get blocked() => _get('blocked');
-
-  EventListenerList get upgradeneeded() => _get('upgradeneeded');
-}