The five-year timer for qualified distributions depends on when you first open up a Roth IRA. Roth 401(k) time doesn't count.
However there's no tax on non-qualified distributions of your principal from a Roth IRA, regardless of how long the account has been open.
For the purpose of Roth IRA ordering rules on funds rolled in from a Roth 401(k), only the amount you originally contributed to the Roth 401(k) counts as principal that can be withdrawn tax-free at any time. Any growth that happened before or after rollover counts as earnings, and will be taxed unless you're old enough and have had a Roth IRA long enough to take a qualified distribution.
