This is a tricky case where iteration matches the last 2 objects
managed by an object manager. When we remove them while iterating,
the last object is not removed because it takes the place of the first
upon removal (side-effect of g_ptr_array_remove_fast()) and the iterator
skips it.
See #388
Until now, object manager could only match pw global properties on
pw global objects, because this is the only available properties set
at the time the registry creates the global.
With this change, the object manager will now bind the proxy
if the type and the pw global properties have matched and will wait
until the proxy is available with all of its properties and tries
the check again.
