int getContentWidth (GC gc, boolean useDisplayText) {
	int contentWidth = 0;
	String text = useDisplayText ? displayText : super.getText ();
	if (text.length () > 0) {
		contentWidth += gc.textExtent (text, SWT.DRAW_MNEMONIC).x;
	}
	if (super.getImage () != null) {
		contentWidth += super.getImage ().getBounds ().width;
		if (text.length () > 0) contentWidth += CTable.MARGIN_IMAGE;
	}
	if (sort != SWT.NONE) {
		contentWidth += parent.arrowBounds.width;
		if (text.length () > 0 || super.getImage () != null) {
			contentWidth += CTable.MARGIN_IMAGE;
		}
	}
	return contentWidth;
}