Resolves a feed id from an id, a feed_N name, a path through /feeds/, or its projection /proc/jobs/feed_N.
feed_N
/feeds/
/proc/jobs/feed_N
What the operator typed.
The feed id, or null when nothing in it names a feed.
Resolves a feed id from an id, a
feed_Nname, a path through/feeds/, or its projection/proc/jobs/feed_N.