Text box tweak: "Delete Current Contents" button (like [X] in practice)

[Isaac Eiland-Hall]

Perhaps to the left or right of text boxes, there could be a small "X" button that would clear the contents of the text box (and, if possible, put the text cursor in the box for typing).

Reasoning: All the time I'm renaming stops and busses and lines and even cities... An alternative would be to support highlighting text with the mouse, but I assume that's not possible (or at least, nobody has wanted it badly enough to code it)... Perhaps this would be an easier option...

Second alternative: Perhaps a double-click in the text field could accomplish this? I don't know if double-clicks are easy to detect, either...