Remove stale files from lib/html/src.

lib/html/src/SVGElementInstance.dart

Index: lib/html/src/SVGElementInstance.dart
diff --git a/lib/html/src/SVGElementInstance.dart b/lib/html/src/SVGElementInstance.dart
deleted file mode 100644
index 7f2782c6f64e7fd0acd3bd02cddc8ddeea0ad9a3..0000000000000000000000000000000000000000
--- a/lib/html/src/SVGElementInstance.dart
+++ /dev/null
@@ -1,24 +0,0 @@
-// Copyright (c) 2011, 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.
-
-// WARNING: Do not edit - generated code.
-
-interface SVGElementInstance extends EventTarget {
-
-  SVGElementInstanceList get childNodes();
-
-  SVGElement get correspondingElement();
-
-  SVGUseElement get correspondingUseElement();
-
-  SVGElementInstance get firstChild();
-
-  SVGElementInstance get lastChild();
-
-  SVGElementInstance get nextSibling();
-
-  SVGElementInstance get parentNode();
-
-  SVGElementInstance get previousSibling();
-}