Extracts the resource ID for child_source, which is supposed to be a stable and unique server-assigned identifier for the
remote resource described by child_source.
If child_source is not actually a child of the collection source owned
by this, the function returns null.
The returned string should be freed with g_free when no longer needed.
| this | |
| child_source |
an Source managed by this |
|
a newly-allocated resource ID for |