Bug 150601 Drillthrough link from pdf(frameset) should link to frameset servlet instead of run.
Description: Drillthrough link from pdf(frameset) should link to frameset servlet instead of run. Steps to reproduce: 1. New a report 2. Insert a label and define a drill through link to other report 3. Preview in Web viewer, click Print as PDF button in viewer toolbar 4. Click drill through link in pdf Expected result: Target report opens through frameset sevlet instead of run servlet. Because the pdf is displayed through frameset servlet. Actual result: Target report opened through run sevlet
viewer/org.eclipse.birt.report.viewer/birt/WEB-INF/classes/org/eclipse/birt/report/service/ReportEngineService.java
* Image directory for report images and charts.
	 */
	private String imageDirectory = null;
	/**
	 * URL accesses images.
	 */
	private String imageBaseUrl = null;
	/**
	 * Image handler instance.
	 */
	private HTMLServerImageHandler imageHandler = null;
	/**
	 * Web app context path.
	 */
	private String contextPath = null;
	/**
	 * Constructor.
	 * 
	 * @param servletConfig
	 * @param config
	 */
	public ReportEngineService( ServletConfig servletConfig )
	{
		System.setProperty( "RUN_UNDER_ECLIPSE", "false" ); 
		if ( servletConfig == null )
		{
			return;
		}
		config = new EngineConfig( );