Bug 176436 Charts Imported from Libraries do not update when libraries change
During a live presentation of BIRT at EclipseCon, we came across a rather embarassing issue. When charts are included in a library, and imported into a report design from a library, any changes to the library instance of the chart do not reflect in the report itself.
model/org.eclipse.birt.report.model/src/org/eclipse/birt/report/model/api/GroupElementHandle.java
* property definitions. If elements do not share any common property,
	 * return an empty list.
	 * 
	 * @return the common properties shared by the given group of elements. If
	 *         elements do not share any common property, or the given list is
	 *         empty, or the list contains any item that is not an instance of
	 *         <code>DesignElementHandle</code>, return an empty list.
	 */
	abstract public List getCommonProperties( );
	/**
	 * Returns an iterator over the common properties. Contents of the iterator
	 * are handles to the common properties, type of them is
	 * <code>GroupPropertyHandle</code>. Note: remove is not support for the
	 * iterator.
	 * 
	 * @return an iterator over the common properties. Contents of the iterator
	 *         are handles to the common properties, type of them is
	 *         <code>GroupPropertyHandle</code>
	 */
	public final Iterator propertyIterator( )
	{
		return new GroupPropertyIterator( getCommonProperties( ) );
	}
	/**
	 * Returns an iterator over the common properties that are visible. Contents
	 * of the iterator are handles to the common properties, type of them is
	 * <code>GroupPropertyHandle</code>. Note: remove is not support for the
	 * iterator.
	 * 
	 * @return an iterator over the common properties. Contents of the iterator