Removing noSuchMethod from Element.

tests/html/html.status

 # 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.
 
 window_open_test: Skip # http://dartbug.com/5151
 
 event_test: Skip  # Issue 1996
 webgl_1_test: Skip  # Issue 1495
 xmldocument_test: Skip  # XML in dart:html is incomplete
 xmlelement_test: Skip  # XML in dart:html is incomplete
@@ skipping 38 matching lines @@
 [ $compiler == dart2js && $runtime == drt && $system == macos]
 audiobuffersourcenode_test: Pass, Fail
 
 [ $compiler == none && $runtime == drt && $system == linux]
 documentfragment_test: Pass, Timeout
 
 [ $runtime == ie9 || $runtime == ie10 || $runtime == safari || $runtime == ff || $runtime == chrome || $runtime == opera ]
 # TODO(vsm): Triage DOM tests.
 shadow_dom_test: Skip # No ShadowDOM support except on tip dartium.
 shadow_dom_layout_test: Skip
-unknownelement_test: Fail # Issue 4189
 
 [ $runtime == dartium || $runtime == chrome || $runtime == ie9 || $runtime == ie10 || $runtime == safari || $runtime == ff || $runtime == opera ]
 history_test: Fail
 
 [$runtime == ie10 ]
 # TODO(efortuna, blois): Triage.
 audiobuffersourcenode_test: Fail
 audiocontext_test: Fail
 canvasrenderingcontext2d_test: Fail, Pass
 contentelement_test: Fail
@@ skipping 198 matching lines @@
 *: Skip
 
 [ $runtime == safari && ($system == linux || $system == windows) ]
 *: Skip
 
 # 'html' tests import the HTML library, so they only make sense in
 # a browser environment.
 [ $runtime == vm ]
 *: Skip
 
-# TODO(jmesserly): now that we have a bot, we need to set up Opera testing.
-
-[ $compiler == dart2js && $runtime == drt ]
-# Unknown error - should investigate.
-unknownelement_test: Fail # Issue 4189
-
 [ $compiler == dart2js ]
 transferables_test: Skip # until isInstance works in dart2js
 
 [ $compiler == dart2js && ($runtime == drt || $runtime == ff) ]
 request_animation_frame_test: Skip # Async test hangs.
 
 [ $compiler == dart2js && ($runtime == drt || $runtime == chrome || $runtime == ff || $runtime == safari) ]
 isolates_test: Skip   # Timeout because leg does not support web workers.
 typed_arrays_1_test: Fail # dart2js doesn't support is checks with generic types.
 
 [ $compiler == dart2js && $runtime == ff ]
 xhr_test: Skip # Timeout
 inner_frame_test: Skip # Timeout
 svg_3_test: Skip # Timeout
 documentfragment_test: Skip # Timeout