Make Storage, Db, and tests more modular.
To prepare for a new backend that doesn't use postgresql. First step toward #1306 (closed).
Test Plan
'tox' still runs the same tests, and doesn't fail.
Migrated from D631 (view on Phabricator)
To prepare for a new backend that doesn't use postgresql. First step toward #1306 (closed).
'tox' still runs the same tests, and doesn't fail.
Migrated from D631 (view on Phabricator)