Bug 121352 The data set binding property cannot be retrieved in report preview layout
In report preview page, the datasource/dataset property binding lists cannot be retrieved. The dataset binding can not work correctly in layout preview because it's value cannot get from the binding list. But in the data set edit page, the binding value can be got. You can refer to the attachment.
model/org.eclipse.birt.report.model/src/org/eclipse/birt/report/model/core/DesignElement.java
* Elements are structured in a hierarchy. The implementation of the
	 * container-to-child relationship must be defined in derived classes. This
	 * base class defines the child-to-container relationship.
	 */
	protected DesignElement container = null;
	/**
	 * Slot in the container in which this element resides.
	 */
	protected int containerSlotID = NO_SLOT;
	/**
	 * Listeners are the objects that want to be notified of events. Contents
	 * are of type Listener. Created only when needed.
	 */
	protected ArrayList listeners = null;
	/**
	 * Values for non-intrinsic property values. The contents are of type
	 * Object.
	 */
	protected Map propValues = new HashMap( );
	/**
	 * Definitions for user-defined properties. Contents are of type
	 * UserPropertyDefn.
	 */
	protected HashMap userProperties = null;
	/**
	 * Support for inheritance. Represents the resolved or unresolved element
	 * that this element extends.
	 */
	protected ElementRefValue extendsRef = null;
	/**