Bug 162841 [regression]Drill-through link to document containing parameters failed in html and pdf
Description: Drill-through link to document containing parameters failed in html and pdf Steps to reproduce: 1. New a report with a report parameter, don't set default value for it. 2. Preview in Web Viewer, input parameter value and save the report document to c:\ 3. New another report, insert a label, set a drill through link on the label, link to the report document. 4. Preview in web viewer, html and pdf, click the link. Expected result: Link to target report. Actual result: In html, a dialog popped up and said "a runtime error has occurred" In pdf, a dialog popped up and said that report parameter has null value. In frameset servlet, both formats are ok. I found that if I set default value for the report parameter in target report, the issue will disappear.
viewer/org.eclipse.birt.report.viewer/birt/WEB-INF/classes/org/eclipse/birt/report/context/ViewerAttributeBean.java
/**
	 * @return the parameter handle
	 */
	public ParameterHandle findParameter( String paramName )
			throws ReportServiceException
	{
		if ( paramName == null )
			return null;
		IReportRunnable runnable = (IReportRunnable) this.reportDesignHandle
				.getDesignObject( );
		ModuleHandle model = null;
		if ( runnable != null )
			model = runnable.getDesignHandle( ).getModuleHandle( );
		if ( model != null )
			return model.findParameter( paramName );
		else
			return null;
	}
	/**
	 * @return the maxRows
	 */
	public int getMaxRows( )
	{
		return maxRows;
	}
	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.birt.report.context.BaseAttributeBean#getReportTitle()
	 */