Bug 121498 When datasource/dataset deleted, the datasource/dataset property binding element haven't been deleted
When deleted the datasource/dataset, the datasource/dataset property binding element haven't been deleted. Expected result: This operation must be a transaction.
model/org.eclipse.birt.report.model/src/org/eclipse/birt/report/model/api/DesignElementHandle.java
* <li>SHORT_LABEL: All the above steps are used. This will ensure there
	 * will be a return value</li>
	 * <li>FULL_LABEL: Besides the return value of SHORT_LABEL, this option
	 * says we need to return additional information. This information is
	 * specific to each kind of element and my include row and column position,
	 * x and y position and so on. To get this, every child element needs to
	 * overwrite this method</li>
	 * </ul>
	 * 
	 * @param level
	 *            the display label detail level
	 * @return the display label of this element in a given level
	 */
	public String getDisplayLabel( int level )
	{
		assert level == DesignElement.USER_LABEL
				|| level == DesignElement.SHORT_LABEL
				|| level == DesignElement.FULL_LABEL;
		return getElement( ).getDisplayLabel( module, level );
	}
	/**
	 * Sorts a list of elements by localized display name.
	 * 
	 * @param list
	 *            the list to sort
	 */
	public static void doSort( List list )
	{
		Collections.sort( list, new Comparator( ) {
			public int compare( Object arg0, Object arg1 )