The way of adding a line to the string. It is used as textDecoration property of GridStyles.
| NONE | "none" | Do not display the line. |
| UNDERLINE | "underline" | Display a line to the bottom of text. |
| OVERLINE | "overline" | Display a line to the top of text. |
| LINE_THROUGH | "lineThrough" | Display a line through the center of text. |