Bug 193875 we can not get an entir url by IHTMLActionHandler
we can not get an entir url by IHTMLActionHandler, so word emitter dose not write the right url. now hyperlink drill through in word emitter doesn't work.
viewer/org.eclipse.birt.report.viewer/birt/WEB-INF/classes/org/eclipse/birt/report/utility/ParameterAccessor.java
* URL parameter name that gives that image rtl option.
	 */
	public static final String PARAM_RTL = "__rtl"; 
	/**
	 * URL parameter name that gives the preview max rows option.
	 */
	public static final String PARAM_MAXROWS = "__maxrows"; 
	/**
	 * URL parameter name that gives the reportlet id.
	 */
	public static final String PARAM_INSTANCEID = "__instanceid"; 
	/**
	 * URL parameter name to indicate whether need to run a reportlet.
	 */
	public static final String PARAM_ISREPORTLET = "__isreportlet";
	/**
	 * URL parameter name to indicate the export encoding.
	 */
	public static final String PARAM_EXPORT_ENCODING = "__exportEncoding";
	/**
	 * URL parameter name to indicate the CSV separator.
	 */
	public static final String PARAM_SEP = "__sep";
	/**
	 * URL parameter name to indicate if fit to page when render report as PDF.
	 */
	public static final String PARAM_FIT_TO_PAGE = "__fittopage";
	/**
	 * URL parameter name to indicate if pagebreak pagination only when render
	 * report as PDF.