The `is_network_only_plugin` and `is_plugin_active` functions are not available in a front-end context and must be specifically loaded. Props oakesjosh. Fixes #52205. Built from https://develop.svn.wordpress.org/trunk@49952 git-svn-id: http://core.svn.wordpress.org/trunk@49651 1a063a9b-81f0-0310-95a4-ce76da25c4cd