Summary: Depends on D20779. Ref T13403. Bad parameters may cause this call to fail without setting an error code; if it does, catch the issue and go down the normal connection error pathway.
Test Plan:
- With "mysql.port" set to "quack", ran `bin/storage probe`.
- Before: wild mess of warnings as the code continued below and failed when trying to interact with the connection.
- After: clean connection failure with a useful error message.
Maniphest Tasks: T13403
Differential Revision: https://secure.phabricator.com/D20780
