Bug 130492 Provide a method to serialize the report with library information.
Currently, when engine generate the report document file, the document does not contain any library information. That will cause many propblem on server side. Model should provide a method to serialize the report with library information to a stream so that the generated report document can contain all information that the report need.
model/org.eclipse.birt.report.model/src/org/eclipse/birt/report/model/core/DesignElement.java
assert value == null || value instanceof ElementRefValue;
		assert prop.getTypeCode( ) == PropertyType.ELEMENT_REF_TYPE;
		return resolveElementReference( module, prop, (ElementRefValue) value );
	}
	/**
	 * Resolves a property structure reference. The reference is the value of a
	 * property of type property structure reference.
	 * 
	 * @param module
	 *            the module information needed for the check, and records any
	 *            errors
	 * @param prop
	 *            the property whose type is structure reference
	 * @return the resolved value if the resolve operation is successful,
	 *         otherwise the unresolved value
	 */
	public StructRefValue resolveStructReference( Module module,
			ElementPropertyDefn prop )
	{
		Object value = propValues.get( prop.getName( ) );
		assert value == null || value instanceof StructRefValue;
		if ( value == null || module == null )
			return (StructRefValue) value;
		StructRefValue ref = (StructRefValue) value;
		if ( ref.isResolved( ) )
			return ref;