Remove stale files from lib/html/src.

lib/html/src/TextEventWrappingImplementation.dart

Index: lib/html/src/TextEventWrappingImplementation.dart
diff --git a/lib/html/src/TextEventWrappingImplementation.dart b/lib/html/src/TextEventWrappingImplementation.dart
deleted file mode 100644
index e83f5d82d7085633a7659da827e383741ac7d6b9..0000000000000000000000000000000000000000
--- a/lib/html/src/TextEventWrappingImplementation.dart
+++ /dev/null
@@ -1,16 +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.
-
-class TextEventWrappingImplementation extends UIEventWrappingImplementation implements TextEvent {
-  TextEventWrappingImplementation._wrap(ptr) : super._wrap(ptr);
-
-  factory TextEventWrappingImplementation(String type, Window view, String data,
-      [bool canBubble = true, bool cancelable = true]) {
-    final e = dom.document.createEvent("TextEvent");
-    e.initTextEvent(type, canBubble, cancelable, LevelDom.unwrap(view), data);
-    return LevelDom.wrapTextEvent(e);
-  }
-
-  String get data() => _ptr.data;
-}