Ruby

• vm_core.h: constify rb_iseq_constant_body::catch_table.
• compile.c (iseq_set_exception_table): catch up this fix.
• iseq.c: ditto.
• vm.c (vm_exec): ditto.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@51365 b2dd03c8-39d4-4d8f-98ff-823fe69b080e