Bug 219483 [Markers] MarkerField needs to support font and colours
Some users want to be able to set the font and colour of an entry in the markers view. We should pass in a ViewerCell for this.
bundles/org.eclipse.ui.ide/src/org/eclipse/ui/internal/views/markers/ExtendedMarkersView.java
*/
	void setPrimarySortField(MarkerField field) {
		TreeColumn[] columns = viewer.getTree().getColumns();
		for (int i = 0; i < columns.length; i++) {
			TreeColumn treeColumn = columns[i];
			if (columns[i].getData(MARKER_FIELD).equals(field)) {
				setPrimarySortField(field, treeColumn);
				return;
			}
		}
		StatusManager.getManager().handle(
				StatusUtil.newStatus(IStatus.WARNING,
						"Sorting by non visible field " 
								+ field.getColumnHeaderText(), null));
	}
	/**
	 * Set the primary sort field to field and update the column.
	 * 
	 * @param field
	 * @param column
	 */
	private void setPrimarySortField(MarkerField field, TreeColumn column) {
		builder.setPrimarySortField(field);
		IWorkbenchSiteProgressService service = (IWorkbenchSiteProgressService) getViewSite()
				.getAdapter(IWorkbenchSiteProgressService.class);
		builder.refreshContents(service);
		updateDirectionIndicator(column, field);
		viewer.refresh();
		reexpandCategories(builder);
	}