Notify DesignTimeUtils about all beans, not only about UIObjects.

Review at http://gwt-code-reviews.appspot.com/1483801

Review by: zundel@google.com

git-svn-id: https://google-web-toolkit.googlecode.com/svn/trunk@10455 8db76d5a-ed1c-0410-87a9-c151d255dfc7