ext/tk/tcltklib.c: adjust nesting

* ext/tk/extconf.rb: check for rb_thread_alive_p and
  rb_thread_check_trap_pending.

* ext/tk/tcltklib.c (rb_thread_alive_p, rb_thread_check_trap_pending):
  define substitutions if not available.

* ext/tk/tcltklib.c (lib_eventloop_core, lib_eventloop_ensure),
  (lib_thread_callback, ip_rbUpdateCommand, ip_rbVwaitCommand),
  (ip_rbTkWaitCommand, call_queue_handler, eval_queue_handler),
  (invoke_queue_handler): adjust nesting.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@39974 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
tcltklib.c: suppress warnings

* ext/tk/tcltklib.c (lib_eventloop_core, lib_thread_callback),
  (ip_rbUpdateCommand, ip_rb_threadUpdateCommand, lib_toUTF8_core),
  (ip_invoke_core): remove unused variables.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@39975 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
* properties.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@39976 b2dd03c8-39d4-4d8f-98ff-823fe69b080e