Prevent resetting active domain without need

I checked how it happened that the active domain is reset in those two places. Here are respective commits: 32920b2f and ac6552da, and it looks like we should simply check whether a domain is previously set before resetting it. Please see MR !130 for the suggested change.

Probably won't be needed anymore once this issue gets merged: 🐛 Arbitrary null value from DomainNegotiator::getActiveDomain() Needs review .

@alex.bukach would you mind explaining a bit more in detail the impact on performance you notice?

@mably I profiled a site and found that resetting and re-negotiating domain in when it was already set took a significant time. You are right, the fix committed for https://www.drupal.org/project/domain/issues/3226427 🐛 Arbitrary null value from DomainNegotiator::getActiveDomain() Needs review already made the same changes I suggested here.

Automatically closed - issue fixed for 2 weeks with no activity.