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 container;
	}
	/**
	 * Caches the child-to-container relationship. The caller must have
	 * validated that the relationship is valid.
	 * <p>
	 * Part of: The containment system.
	 * 
	 * @param obj
	 *            the container to set
	 * @param slot
	 *            the slot within the container where this element resides
	 */
	public void setContainer( DesignElement obj, int slot )
	{
		container = obj;
		containerSlotID = slot;
	}
	/**
	 * Gets the property data for either a system-defined or user-defined
	 * property.
	 * <p>
	 * Part of: Property system and user-defined property system
	 * 
	 * @param propName
	 *            The name of the property to lookup.
	 * @return The property definition, or null, if the property is undefined.
	 */
	public ElementPropertyDefn getPropertyDefn( String propName )