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
e = e.getContainer( );
		}
		
		return getSessionDefaultValue( module, prop );
	}
	/**
	 * Gets the session default value of the specified property if it is style
	 * property.
	 * 
	 * @param module
	 *            module
	 * @param prop
	 *            definition of the property to get
	 * @return The session default property value, or null if no default value
	 *         is set.
	 */
	private Object getSessionDefaultValue( Module module,
			ElementPropertyDefn prop )
	{
		if ( prop.isStyleProperty( ) )
		{
			
			return module.session.getDefaultValue( prop.getName( ) );
		}
		return null;
	}
	/**
	 * Gets selector of the given slot of this element. The selector is kind of
	 * predefined style, and its style property value can be applied on contents
	 * of the given slot of this element depending on whether property can be