* Abandon auto search on undefined name
These might arise from names in other modules that haven't been
imported. But it's going to be an error whatever, so give up straight
away. Fixes#1925
* Fix typo
* Fix test source
* Record possible cause when we can't solve a goal
Normally, it's just because we searched and failed. But maybe sometimes,
it's because there's an undefined name, in which case, we can include
this in the error message.
This is good to record because it means we don't abandon elaboration at
the wrong time! Say, if a search fails due to an undefined name, but it
was only in one branch of an ambiguous elaboration.
* Add necessary arguments for perf009 test
