Mark jQuery methods as experimental.

tools/dom/templates/html/impl/impl_Element.darttemplate

 // 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.
 
 part of $LIBRARYNAME;
 
 class _ChildrenElementList extends ListBase<Element> {
   // Raw Element.
   final Element _element;
   final HtmlCollection _childElements;
@@ skipping 1200 matching lines @@
   @Experimental()
   CssRect get marginEdge => new _MarginCssRect(this);
 
   /**
    * Provides the coordinates of the element relative to the top of the
    * document.
    *
    * This method is the Dart equivalent to jQuery's
    * [offset](http://api.jquery.com/offset/) method.
    */
+  @Experimental()
   Point get documentOffset => offsetTo(document.documentElement);
 
   /**
    * Provides the offset of this element's [borderEdge] relative to the
    * specified [parent].
    *
    * This is the Dart equivalent of jQuery's
    * [position](http://api.jquery.com/position/) method. Unlike jQuery's
    * position, however, [parent] can be any parent element of `this`,
    * rather than only `this`'s immediate [offsetParent]. If the specified
    * element is _not_ an offset parent or transitive offset parent to this
    * element, an [ArgumentError] is thrown.
    */
+  @Experimental()
   Point offsetTo(Element parent) {
     return Element._offsetToHelper(this, parent);
   }
 
   static Point _offsetToHelper(Element current, Element parent) {
     // We're hopping from _offsetParent_ to offsetParent (not just parent), so
     // offsetParent, "tops out" at BODY. But people could conceivably pass in
     // the document.documentElement and I want it to return an absolute offset,
     // so we have the special case checking for HTML.
     bool foundAsParent = identical(current, parent) || parent.tagName == 'HTML';
@@ skipping 183 matching lines @@
   const ScrollAlignment._internal(this._value);
   toString() => 'ScrollAlignment.$_value';
 
   /// Attempt to align the element to the top of the scrollable area.
   static const TOP = const ScrollAlignment._internal('TOP');
   /// Attempt to center the element in the scrollable area.
   static const CENTER = const ScrollAlignment._internal('CENTER');
   /// Attempt to align the element to the bottom of the scrollable area.
   static const BOTTOM = const ScrollAlignment._internal('BOTTOM');
 }