Patch: add extensions directory contents to VMClassLoader class path.

[Andrew Haley]

Ranjit Mathew writes:
 > 
 > Yes, that was the problem - if I just create a dummy
 > $GCC_DIR/share/java/ext folder, the segfault disappears
 > and it reappears if I delete this folder.
 > 
 > If I just protect your code with a "dir.exists()", then
 > things start working fine again.

Yes, but this just papers over the real problem, which is why the
segfault wasn't caught.

Andrew.