Actually, there is `$wgSolrPort` defined when search is enabled in `CommonExtensions.php` but it changes depending on other variables as well. I wanted to move its definition to `CommonSettings.php` and use it instead of `$wgSolrDefaultPort` but it didn't work. Take a look at this changes, please:  https://github.com/Wikia/app/commit/4c406b51b44af1fe65226ecd1cb7a6d92f599b46

I think they're OK for now. But we I'm not sure if we should have two "port" variables: `$wgSolrPort` and `$wgSolrDefaultPort`. There are also places in the code when other hardcoded numbers appear: `8180` or `6081`.