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
resolveStyle( targetDesign, target, source );
		}
	}
	/**
	 * if there is external resource file set for the report, localized all
	 * display property value when serialize the report.
	 * 
	 * @param sourceDesign
	 *            the source design from which to get the copy
	 * @param target
	 *            the target element to resolve the embedded image
	 * @param source
	 *            the source element
	 */
	static void localizeExternalStringProperty( ReportDesign sourceDesign,
			DesignElement target, DesignElement source )
	{
		assert sourceDesign != null && target != null && source != null;
		if ( sourceDesign.getProperty( sourceDesign.getRoot( ),
				ReportDesign.INCLUDE_RESOURCE_PROP ) == null )
			return;
		if ( source instanceof Label )
		{
			String resourcekey = source.getStringProperty( sourceDesign,
					Label.TEXT_ID_PROP );
			if ( resourcekey == null )
				return;
			String displayValue = sourceDesign.getMessage( resourcekey );
			target.setProperty( Label.TEXT_PROP, displayValue );
			target.setProperty( Label.TEXT_ID_PROP, null );