Bug 1878577 - Ensure private storage repo is always cleaned up, even with PBM...

  ScopedLogExtraInfo scope{ScopedLogExtraInfo::kTagContext,

                           "dom::quota::QuotaManager::Shutdown"_ns};

  // We always need to ensure that firefox does not shutdown with a private

  // repository still on disk. They are ideally cleaned up on PBM session end

  // but, in some cases like PBM autostart (i.e.

  // browser.privatebrowsing.autostart), private repository could only be

  // cleaned up on shutdown. ClearPrivateRepository below runs a async op and is

  // better to do it before we run the ShutdownStorageOp since it expects all

  // cleanup operations to be done by that point. We don't need to use the

  // returned promise here because `ClearPrivateRepository` registers the

  // underlying `ClearPrivateRepositoryOp` in `gNormalOriginOps`.

  ClearPrivateRepository();

  // This must be called before `flagShutdownStarted`, it would fail otherwise.

  // `ShutdownStorageOp` needs to acquire an exclusive directory lock over

  // entire <profile>/storage which will abort any existing operations and wait

  // for all existing directory locks to be released. So the shutdown operation

  // will effectively run after all existing operations.

  // We don't need to use the returned promise here because `ShutdownStorage`

  // registers `ShudownStorageOp` in `gNormalOriginOps`.

  // Similar, to ClearPrivateRepository operation above, ShutdownStorageOp also

  // registers it's operation in `gNormalOriginOps` so we don't need to assign

  // returned promise.

  ShutdownStorage();

  flagShutdownStarted();