[svn r330] Implemented synchronized statements. Changed the tryfinally handlers to a more generalized EnclosingHandler. Changed ClassInfoS to be mutable so they can be used as locks. Added new BB after throw ala return/break etc.

module bug2;
struct Vec { Vec barf() { return Vec(); } }
class test { this(Vec whee) { } }
void main() { Vec whee; new test(whee.barf()); }