Bug 122850 Table/list should not be able to be inserted in Master Page mode.
Description: Table/list should not be able to be inserted in Master Page mode. Steps to reproduce: 1. New a report and transfer to Master Page mode. 2. New a datasource and dataset 3. Drag a list/table to page header/footer, bind it to dataset and drag some columns inside. 4. Save and preview Expected result: Insert list/table item in master page should be forbidden. Actual result: They are allowed and preview showed "undefine" in page
model/org.eclipse.birt.report.model/src/org/eclipse/birt/report/model/core/DesignElement.java
* @return The property value, or null if no value is set.
	 */
	public Object getPropertyFromSelector( Module module,
			ElementPropertyDefn prop, String selector )
	{
		assert module != null;
		if ( selector == null )
			return null;
		
		StyleElement style = module.findStyle( selector );
		if ( style != null )
		{
			return style.getLocalProperty( module, prop );
		}
		return null;
	}
	/**
	 * Returns the property value which is related to element selector. It is
	 * from the selector style.
	 * 
	 * @param module
	 *            the module
	 * @param prop
	 *            the definition of property
	 * @return the property value, or null if no value is set.
	 */
	protected Object getPropertyFromSelfSelector( Module module,
			ElementPropertyDefn prop )
	{
		String selector = ( (ElementDefn) getDefn( ) ).getSelector( );