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
* @param propName
	 *            name of the property to set. Must be valid. Can be a
	 *            system-defined or user-defined property name.
	 * @return the property value, or null if no value is set
	 */
	public Object getLocalProperty( Module module, String propName )
	{
		ElementPropertyDefn prop = getPropertyDefn( propName );
		if ( prop == null )
			return null;
		return getLocalProperty( module, prop );
	}
	/**
	 * Gets a property value given its definition. This version checks only this
	 * one object. That is, it gets the "local" property value. The property
	 * name must also be valid for this object.
	 * <p>
	 * Part of: Property value system.
	 * 
	 * @param module
	 *            the module
	 * @param prop
	 *            The property definition.
	 * @return The property value, or null if no value is set.
	 */
	public Object getLocalProperty( Module module, ElementPropertyDefn prop )
	{
		if ( prop.isIntrinsic( ) )
		{