Bug 121111 Bad event handler class name does not cause an error
Open a report design, open any Data Set's Property editor. Type in an invalid Java class name for the "Event Handler Class" property, say "aaa". Preview a report that uses that Data Set. The report executes normally. No error is shown. Event handlers are an integral part of a report design, and if a script handler class is not found, or if the handler throws a runtime exception, Report Engine should either stop the report execution, or show the error message in the generated report. (Tested with the 2005-12-15 nightly build)
engine/org.eclipse.birt.report.engine/src/org/eclipse/birt/report/engine/executor/ExecutionContext.java
* @see org.eclipse.birt.report.engine.executor.IPrensentationContext#getParams()
	 */
	public Map getParams( )
	{
		return params;
	}
	/**
	 * Loads scripts that are stored in an external file. Used to support
	 * include-script. Each script file should be load only once. and the script
	 * in the file must be encoded in UTF-8.
	 * 
	 * @param fileName
	 *            script file name
	 */
	public void loadScript( String fileName )
	{
		File script = new File( report.getBasePath( ), fileName );
		
		try
		{
			FileInputStream in = new FileInputStream( script );
			byte[] buffer = new byte[in.available( )];
			in.read( buffer );
			execute( new String( buffer, "UTF-8" ), fileName, 1 ); 
			in.close( );
		}
		catch ( IOException ex )
		{
			log.log( Level.SEVERE,
					"loading external script file " + fileName + " failed.",