Benefits:
- nmc_client_new_async*() allows to set properties on the NMClient
instance before calling g_async_initable_init_async().
It also allows to subscribe to any signals (like NM_CLIENT_DEVICE_ADDED)
before actually iterating the GMainContext. This is a sensible and
supported thing to do!
- nmc_client_new_waitsync() iterates the GMainContext until the (async)
initialization is complete. That is different from synchronous nm_client_new(),
which does not iterate the caller's GMainContext, and hence needs an
internal context to ensure the order of events is honored.
- nmc_client_new_waitsync() always returns the NMClient instance, even
if initialization fails.
That is useful if you need the nm_client_get_context_busy_watcher() instance
to ensure all pending messages are completed.
9e10b4f699