Blender Git Loki

Fix T87567: Crash adding item in empty attribute search

The function applying the search used the dummy search info for when
the item doesn't exist even when there was no UI data associated with
the node at all.

A fix is to only add the search menu when there is attribute info
stored for the node. This is something I wanted to do anyway, since
it makes it look more purposeful when there are no attribute info
for a node, less like a bug.

Differential Revision: https://developer.blender.org/D11016