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
* @return
	 */
	private static boolean isLocalImage( String imageName,
			ReportDesign sourceDesign )
	{
		StructureDefn defn = (StructureDefn) MetaDataDictionary.getInstance( )
				.getStructure( EmbeddedImage.EMBEDDED_IMAGE_STRUCT );
		if ( StructureRefUtil.findNativeStructure( sourceDesign, defn,
				imageName ) != null )
			return true;
		return false;
	}
	/**
	 * Resolves data source reference 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 data source
	 * @param sourceDesign
	 *            the source design from which to get the copy
	 * @param target
	 *            the target element to resolve the data source
	 * @param source
	 *            the source element
	 */
	static void resolveDataSource( ReportDesign targetDesign,
			ReportDesign sourceDesign, DesignElement target,
			DesignElement source )
	{