Bug 113938 Report is marked dirty when open/close cascading parameter dialog without doing any operation on it
description: Report is marked dirty when open/close cascading parameter dialog without doing any operation on it steps to reproduce: 1.new a cascading parameter group 2.save the reprot 3.double click the cascading parameter to bring out edit box 4.click OK to close edit box actual result: Report has been marked dirty expected result: No dirty marked for that no operations done in edit parameter dialog
UI/org.eclipse.birt.report.designer.ui/src/org/eclipse/birt/report/designer/ui/dialogs/CascadingParametersDialog.java
displayFormat = choiceSet.findChoice( formatCategroy )
					.getDisplayName( );
			if ( formatPattern != null )
			{
				displayFormat += ":  " + formatPattern; 
			}
		}
		formatField.setText( "" + displayFormat ); 
		changeFormat.setEnabled( choiceSet != null );
		if ( selectedParameter != null )
		{
			try
			{
				doPreview( formatPattern == null ? formatCategroy
						: formatPattern );
				String format = formatCategroy;
				if ( formatPattern != null )
				{
					format += ":" + formatPattern; 
				}
				selectedParameter.setFormat( format );
			}
			catch ( SemanticException e1 )
			{
				ExceptionHandler.handle( e1 );
			}
		}
	}
	private void doPreview( String pattern )
	{