This code is bogus in multiple ways:
* It scales text based on ascent or descent, but this makes no sense
  as those control line height and nothing else, if one is to scale two
  different fonts to “fit” together, cap or x height would be more
  appropriate. This results in some text being ridiculously shrunk.
* Not only that, but it is comparing apples to oranges; original font
  ascent/descent with the bounding box of the fallback glyphs, which
  results in different scale ratios depending on the shape of the glyphs
  at hand, which leads to all sorts of funny and irregular text.
* Even worse, the PDF export is completely broken in this case; it uses
  the scaled down glyph widths but the unscaled font size, resulting in
  cramped unreadable text.

Change-Id: Iaa6117ecfdad8388887d9a03b538e7327544ad5e
Reviewed-on: https://gerrit.libreoffice.org/4293Reviewed-by: Bosdonnat Cedric <cedric.bosdonnat@free.fr>
Tested-by: Bosdonnat Cedric <cedric.bosdonnat@free.fr>
Reviewed-by: Caolán McNamara <caolanm@redhat.com>
Tested-by: Caolán McNamara <caolanm@redhat.com>