Created attachment 7970 
Fix uninitialized variable

With GCC and also Clang with the latest release 0.2.2 (and also previous) a warning is displayed because erro_code variable is not initialized in tumblerd/  tumbler-group-scheduler.c.

  CC       tumblerd-tumbler-group-scheduler.o
tumbler-group-scheduler.c: In function 'tumbler_group_scheduler_thread':
tumbler-group-scheduler.c:610:7: warning: 'error_code' may be used uninitialized in this function [-Wmaybe-uninitialized]
       g_signal_emit_by_name (request->scheduler, "error", request->handle,
       ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
                              failed_uris, error_code, message->str,
                              ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
                              request->origin);
                              ~~~~~~~~~~~~~~~~