Theme_Upgrader
Core class used for upgrading/installing themes.
Core class used for upgrading/installing themes.
Upgrade several themes at once.
Checks that the package source contains a valid theme.
Check if a child theme is being installed and we need to install its parent.
Turn off maintenance mode after upgrading the active theme.
Turn on maintenance mode before attempting to upgrade the active theme.
Delete the old theme during an upgrade.
Don’t display the activate and preview actions to the user.
Install a theme package.
Initialize the installation strings.