Java: Don't mangle "$" characters in identifier names

[Alexandre Petit-Bianco]

> This is unfortunate since using `.' instead probably isn't what we
> want.  But perhaps the final sentence here is simply out of date.
> 
> I think updating the C++ compiler is the right approach.

I think so too. Note that even if treating `$' right would be nice,
the ultimate goal for the C++ compiler mangling code would be to
do unicode mangling as we agreed we would:

  http://gcc.gnu.org/ml/java/2001-01/msg00227.html

./A