Moved most of html lib generating scripts into tools.

sdk/lib/html/templates/html/impl/impl_Event.darttemplate

Index: sdk/lib/html/templates/html/impl/impl_Event.darttemplate
diff --git a/sdk/lib/html/templates/html/impl/impl_Event.darttemplate b/sdk/lib/html/templates/html/impl/impl_Event.darttemplate
deleted file mode 100644
index c1cf0961fa122cae2a8c1e766c24f8f949fc3d5f..0000000000000000000000000000000000000000
--- a/sdk/lib/html/templates/html/impl/impl_Event.darttemplate
+++ /dev/null
@@ -1,20 +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.
-
-// WARNING: Do not edit - generated code.
-
-part of html;
-
-/// @domName $DOMNAME
-class $CLASSNAME$EXTENDS$IMPLEMENTS$NATIVESPEC {
-  // In JS, canBubble and cancelable are technically required parameters to
-  // init*Event. In practice, though, if they aren't provided they simply
-  // default to false (since that's Boolean(undefined)).
-  //
-  // Contrary to JS, we default canBubble and cancelable to true, since that's
-  // what people want most of the time anyway.
-  factory $CLASSNAME(String type, [bool canBubble = true, bool cancelable = true]) =>
-      _$(CLASSNAME)FactoryProvider.create$CLASSNAME(type, canBubble, cancelable);
-$!MEMBERS
-}