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
* inherit the property from its parent element, style, or from the default
	 * value for the property.
	 * 
	 * @throws SemanticException
	 *             if the property is not defined on this element
	 */
	public void clearAllProperties( ) throws SemanticException
	{
		List props = getDefn( ).getProperties( );
		for ( int i = 0; i < props.size( ); i++ )
		{
			PropertyDefn propDefn = (PropertyDefn) props.get( i );
			setProperty( propDefn.getName( ), null );
		}
	}
	/**
	 * Returns <code>true</code> if this element has any locally-defined
	 * property values. Returns <code>false</code> otherwise.
	 * 
	 * @return True if the element has property values, false if not.
	 */
	public boolean hasLocalProperties( )
	{
		return getElement( ).hasLocalPropertyValues( );
	}
	/**
	 * Adds a user-defined property definition. The property definition must
	 * have a valid name and property type. The other attributes can be set
	 * either before or after adding the property to the element. The
	 * application can modify the property definition directly before adding the