NMClient was watching to see whether NetworkManager was running, but
its parent class NMObject was already doing that anyway, so NMClient
doesn't need to do it itself.

This also requires making NMClient:init_async() wait for NMObject's
init_async() code to finish before calling GetPermissions, rather than
running the two in parallel like before (since we don't know if NM is
running or not until after NMObject's init_async() returns). This is
probably more correct anyway in terms of inheritance, and it's not as
much slower than the original code as it sounds, since previously
we were calling NameHasOwner twice (in serial) anyway.