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/context/BaseAttributeBean.java
* indicate whether the document is existed.
	 */
	public boolean documentInUrl = false;
	/**
	 * Abstract methods.
	 */
	abstract protected void __init( HttpServletRequest request )
			throws Exception;
	abstract protected IViewerReportService getReportService( );
	abstract protected void __finalize( ) throws Throwable;
	/**
	 * Default constructor.
	 */
	public BaseAttributeBean( )
	{
	}
	/**
	 * Constructor.
	 */
	public BaseAttributeBean( HttpServletRequest request )
	{
		try
		{
			init( request );
		}
		catch ( Exception e )
		{
			this.exception = e;
		}
	}