Acount for all non-negative spaces used by lyx

Acount for all non-negative spaces used by lyx

The unicode representation in an ascii-string string is
\302\240                                Normal space
\342\200\257                            Non-breaking Thin (1/6 em)
\342\200\213\342\200\205\342\200\213    Medium(2/9 em)
\342\200\213\342\200\204\342\200\213    Thick (5/18 em)
\342\201\240\342\200\202\342\201\240    Half Quad(0.5 em)
\342\200\203                            Quad(1 em)
\342\200\203\342\200\203                Double Quad(2 em)
\342\220\243                            Visible space

'Double Quad' counts as 2 spaces, all others count as 1 space in the search regex