We had a few different patterns in our codebase. This unifies all of
them to a single helper. We had not one but two (!) different pieces
of code also trying to create dumps if the assertion failed. I've chosen
to toss both of those, since I believe one of two things to be true:

1. The underlying bugs have been fixed, and it's probable the dumping
   code no longer works.
2. The underlying bugs havent been fixed, but we're clearly not hitting
   that fail code.