Something wrong in "ascii-math". when write anything in overbar

[Nits7029]

@arnog

Steps to Reproduce

1. When i tried to get ascii-math of this type of latex.
2. I got ascii-math value just blank string.

Actual Behavior

I'm just getting a blank string for this type of Latex. The overline, underline and overrightarrow wrapped Latex is ignored in ascii-math.

Environment

This is not happening before. it would just happening after the last reaslese