Mouse highlight in bidi-reordered text

[Eli Zaretskii]

I committed a few minutes ago to the trunk revision 102053, which
makes the mouse highlight support bidi-reordered text, both in
left-to-right and in right-to-left paragraphs.  This turned out to be
a much larger job than I originally anticipated; in particular, it
required a complete rewrite of a couple of functions and introduction
of 2 new functions.  The modified code is run for unidirectional text
as well, so please report as bugs any anomalies you see in mouse
highlight which are not present in Emacs 23.x.

TIA