Maybe an unnecessary assertion in dbus-gmain.c

[Zhu Yanhai]

Hi all,
The assertion in dbus-gmain.c:253 said dbus_watch_get_data(watch) should 
be NULL, however connection_setup_add_watch() will call into 
dbus_watch_set_data() then, which will free watch->data if 
watch->free_data_function exists, which conflicts with the assertion.
Do you think the assertion is wrong?

(I have filed a bug at 
https://bugs.freedesktop.org/show_bug.cgi?id=29663, the assertion could 
be triggered sometimes)

Thanks,
Zhu Yanhai