ufo: must scale max_err_em list by UPEM
ufo: must scale max_err_em list by UPEM

When the 'max_err_em' argument is a float, we multiply it
by the font.info.unitsPerEm. However we were not doing it when
the argument is a list of floats...

fonttools/fonttools,googlefonts/cu2qu,googlei18n/cu2qu,googlefonts/fonttools