MS Word's UI is a bit confusing for RTL because the only place you
can set it (at least in Word 2003) is on the Normal paragraph
style - everywhere else the control is grayed out.

Add a test that very specifically tests the impact of Normal style.
The document does not use the "default" style at all, because
the style used is based on -none-. Normal is set to RTL - does
that mean that the whole document should be RTL or that
Left/Right should swap?

No. Parentless style provides LTR in MSWord, and thus the LO code
that ExchangeLeftRight() based on DefaultStyle's bidi setting was
wrong. Yes, it is determined by style/DocDefault settings, but
not by DefaultStyle in particular.

Change-Id: I000953e51d3d919f73aa1e97df63f266d15447b2
Reviewed-on: https://gerrit.libreoffice.org/57859
Tested-by: Jenkins
Reviewed-by: Justin Luth <justin_luth@sil.org>