UTDs after following permalinks are not resolved after the key is received

[richvdh]

Much the same as #5703 and #5798. If you follow a permalink to an event, you will see a "focussed timeline" of events around the permalink. Any messages that are UTD will cause an attempt to download the key from key backup. But if the key is successfully received, there is no attempt to update the event on screen.

[richvdh]

(This is due to #5954, which is a known thing. Just opening this to keep track of the fact it causes UTDs, and for symmetry with #5703 and #5798)

[bnjbvr]

#6185 should fix this.