Description of problem:
FreeIPA/IdM installations which were created with directory server preceding DS
1.3.3.0 doesn't have DS whoami plugin enabled.

Whoami plugin is required for whoami IPA API call which is part of Web UI
startup. Whoami command is executed after login to get who is the user. With
missing plugin entablement this command fails with protocol error and thus
loading of Web UI fails.

In httpd error log the error is:

ipa: ERROR: non-public: PROTOCOL_ERROR: {'info': 'unsupported extended
operation', 'desc': 'Protocol error'}

Workaround:
Enable the plugin by modifying dse.ldif when DS is shutdown. Or by executing
LDAP mod operation as Directory Manager with following ldif:

# whoami, plugins, config
dn: cn=whoami,cn=plugins,cn=config
cn: whoami
nsslapd-plugin-depends-on-type: database
nsslapd-pluginDescription: whoami extended operation plugin
nsslapd-pluginEnabled: on
nsslapd-pluginId: whoami-plugin
nsslapd-pluginInitfunc: whoami_init
nsslapd-pluginPath: libwhoami-plugin
nsslapd-pluginType: extendedop
nsslapd-pluginVendor: 389 Project
nsslapd-pluginVersion: 1.3.6.1
objectClass: top
objectClass: nsSlapdPlugin
objectClass: extensibleObject


Expected results:
If whoami plugin is enabled during IPA upgrade if it is not enabled.