Build is not triggered if diff repository is not set

[metaflow]

For example https://reviews.llvm.org/D90930?id=305761
We might need to figure out why that happens an check how many diffs are MIA

[poelmanc]

This just bit me too, e.g. https://reviews.llvm.org/D68682?id=321451. I believed the Repository field was supposed to be left blank per the LLVM Phabricator instructions at https://llvm.org/docs/Phabricator.html:

Leave this first Repository field blank. (We’ll fill in the Repository later, when sending the review.)
...
Leave the Repository field blank. (We previously filled out the Repository for the review request.)

[metaflow]

I have updated herald rule to trigger check if repository does not match any other known repo:

Repository is not any of rZORG LLVM Github Zorg, rW llvm-www, rLNT LNT, rT test-suite

so now it should trigger on unset repository as well

https://reviews.llvm.org/H511 for "beta" users
https://reviews.llvm.org/H576 for everyone else

[metaflow]

here is an example of build triggered by a revision w/ no repository set https://reviews.llvm.org/D97357?id=325980

[ldionne]

Nice, thanks for fixing this. It's been a source of churn in libc++ - glad to see it's fixed.