bug 452680: BasicPropertySupport & WeakEventListener 
https://bugs.eclipse.org/bugs/show_bug.cgi?id=452680

Change-Id: Ie325fd5d24d310cb68c83b967f6863fdfe0c3736
Signed-off-by: Judith Gull <jgu@bsiag.com>
Reviewed-on: https://git.eclipse.org/r/36986
Tested-by: Hudson CI