MSO uses undocumented properties that seem to map to o:hr and o:hrpct
from .docx (including differences between .docx spec and implementation),
so treat horizontal rule width the same way in .doc too. Also remove
the guesswork for #i17200# that is not quite correct and no longer needed.

Change-Id: Ibec543fa1679ca0b20e86ef6b4f77147b18dff7e