Bug 153378 [Regression]Label text won't show up when the text key is not found
Steps to reproduce: 1.Add a label, set text to "aaa" 2.Add a resource file "a" to the report, add a text key "k1" which is not in the a.properties to the label 3.Preview in Web Viewer Expected result: Label display "aaa" when the text key is not found Actual result: Nothing in preview
model/org.eclipse.birt.report.model/src/org/eclipse/birt/report/model/api/util/DocumentUtil.java
DesignElement source = sourceDesign
					.getElementByID( target.getID( ) );
			if ( source != null )
				resolveElementReference( targetDesign, sourceDesign, target,
						source );
		}
	}
	/**
	 * Resolves all the element references in the target element. This method
	 * will copy the resolved element reference from the source element to the
	 * target design.
	 * 
	 * @param targetDesign
	 *            the target design to add the copied element
	 * @param sourceDesign
	 *            the source design from which to get the copy
	 * @param target
	 *            the target element to resolve the element references
	 * @param source
	 *            the source element
	 */
	static void resolveElementReference( ReportDesign targetDesign,
			ReportDesign sourceDesign, DesignElement target,
			DesignElement source )
	{
		if ( targetDesign == null || target == null || source == null )
			return;
		assert target.getDefn( ) == source.getDefn( );
		if ( source instanceof CascadingParameterGroup
				|| source instanceof ScalarParameter )