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
if ( slotHandle != null )
			slotHandle.add( child );
	}
	/**
	 * Returns the methods defined on the element definition.
	 * 
	 * @return List contains the methods.
	 * 
	 */
	public List getMethods( )
	{
		return getElement( ).getDefn( ).getMethods( );
	}
	/**
	 * Sets a bunch of property values on the element. If this operation should
	 * be treated as a whole, execution should be in a transaction.
	 * 
	 * @param properties
	 *            a Map store the property values keyed by the property name.
	 * @throws SemanticException
	 *             if the property is undefined on the element or the value is
	 *             invalid.
	 * @see #setProperty(String, Object)
	 */
	public void setProperties( Map properties ) throws SemanticException
	{
		if ( properties == null )
			return;
		for ( Iterator iter = properties.keySet( ).iterator( ); iter.hasNext( ); )
		{