Follow-up to r81439, works up to installing the admin user then dies with:
Creating administrator user account...
Mediawiki tried to access the database via wfGetDB(). This is not allowed.
Backtrace:
#0 /var/www/testsite.com/w/includes/GlobalFunctions.php(3020): LBFactory_Fake->getMainLB(false)
#1 /var/www/testsite.com/w/includes/GlobalFunctions.php(3010): wfGetLB(false)
#2 /var/www/testsite.com/w/includes/User.php(2558): wfGetDB(-1)
#3 /var/www/testsite.com/w/includes/installer/Installer.php(1383): User->idForName()
#4 [internal function]: Installer->createSysop(Object(PostgresInstaller))
#5 /var/www/testsite.com/w/includes/installer/Installer.php(1293): call_user_func(Array, Object(PostgresInstaller))
#6 /var/www/testsite.com/w/includes/installer/WebInstallerPage.php(1022): Installer->performInstallation(Array, Array)
#7 /var/www/testsite.com/w/includes/installer/WebInstaller.php(243): WebInstaller_Install->execute()
#8 /var/www/testsite.com/w/config/index.php(46): WebInstaller->execute(Array)
#9 /var/www/testsite.com/w/config/index.php(14): wfInstallerMain()
#10 {main}