Bug 304645 'Restore Defaults' does not work on 'Resource Filters' properties page
I20100302-0800. 'Restore Defaults' does not work on 'Resource Filters' properties page.
bundles/org.eclipse.ui.ide/src/org/eclipse/ui/internal/ide/dialogs/ResourceFilterGroup.java
IDEWorkbenchMessages.ResourceFilterPage_downButtonLabel,
					null));
			data = new GridData(SWT.FILL, SWT.FILL, false, false);
			downButton.setLayoutData(data);
			setButtonDimensionHint(downButton);
			downButton.addSelectionListener(new SelectionListener() {
				public void widgetDefaultSelected(SelectionEvent e) {
				}
				public void widgetSelected(SelectionEvent e) {
					handleDown();
				}
			});
		}
	}
	private void refreshEnablement() {
		addButton.setEnabled(true);
		ISelection selection = filterView.getSelection();
		IStructuredSelection structuredSelection = null;
		if (selection instanceof IStructuredSelection)
			structuredSelection = ((IStructuredSelection) selection);
		removeButton.setEnabled(structuredSelection != null
				&& structuredSelection.size() > 0);
		editButton.setEnabled(structuredSelection != null
				&& structuredSelection.size() == 1);
		if (upButton != null)
			upButton.setEnabled(structuredSelection != null
					&& (structuredSelection.size() > 0)
					&& !isFirst(structuredSelection.getFirstElement()));
		if (downButton != null)
			downButton.setEnabled(structuredSelection != null