Invisible bar line and wide lyric produces "mis-predicted force" error.

[Aaron Hill]

I encountered this when typesetting a piece that needs fairly wide 
stanza markings.  One piece worked fine, while another failed with 
"mis-predicted force" errors.  While reducing the repro, it seemed the 
main difference was the presence of an invisible bar line (i.e. \bar "") 
earlier in the score along with some wide lyrics.  Without that bar line 
present or by narrowing the stanza marking, the piece that had failed no 
longer reported any errors.

For reference, I am using version 2.19.80 (MinGW) on Windows 10 Pro 
64-bit (16299.371).

Here is a minimal repro using a simple lyric instead of a stanza 
marking:

%%%%
% The combination of an invisible bar line and a wide lyric produces:
% "programming error: mis-predicted force, 108.120472 ~= 108.482555"
\version "2.19.80"
{ r2 \bar "" c'2 } \addlyrics { "mmmmmm" }
%%%%

The only references I could find to "mis-predicted force" are in 
relation to an issue regarding grace notes and possible floating-point 
arithmetic issues in the Windows/MinGW build.  Presuming this is 
related, here is hoping this repro can help shed some light on the 
underlying issue.

-- Aaron Hill