Bug 146352 support cancel execution for "view report ..." tool bar and menu actions.
Current "view report as HTML" and "view report as PDF" in the menu tool bar uses RunAndRender task to stream back the report output. As a result, total page count is not available when the report is being streamed back. Please change these two requests to use Run task and then render task to generate HTML or PDF, so that the total page count is calculate. preview tab could continue to use RunAndRender task, since it is for preview.
viewer/org.eclipse.birt.report.viewer/birt/WEB-INF/classes/org/eclipse/birt/report/service/ViewerHTMLActionHandler.java
/**
	 * Document instance.
	 */
	protected IReportDocument document = null;
	/**
	 * Locale of the requester.
	 */
	protected Locale locale = null;
	/**
	 * Page number of the action requester.
	 */
	protected long page = -1;
	/**
	 * if the page is embedded, the bookmark should always be a url to submit.
	 */
	protected boolean isEmbeddable = false;
	/**
	 * RTL option setting by the command line or URL parameter.
	 */
	protected boolean isRtl = false;
	/**
	 * if wanna use the master page, then set it to true.
	 */
	protected boolean isMasterPageContent = true;
	/**
	 * Constructor.
	 */
	public ViewerHTMLActionHandler( )
	{
	}