Description of problem:
sss_cache -E command invalidates all the user entries in main sysdb cache and timestamp cache, however the group entry in sysdb main cache is unaffected. sss_cache invalidates only the timestamp cache group entries.

Version-Release number of selected component (if applicable):
sssd-1.14.0-34.el7.x86_64

How reproducible:
Always

Steps to Reproduce:
1. Setup 389-ds ldap server and add a test group to it.

2. Setup Rhel-7.3 with SSSD client against LDAP provider.
Sample sssd.conf :
---------------------------------------------
[sssd]
config_file_version = 2
domains = LDAP
services = nss, pam

[domain/LDAP]
id_provider = ldap
auth_provider = ldap
debug_level = 0xFFF0
cache_credentials = FALSE
ldap_uri = ldaps://<LDAP_SERVER>
ldap_tls_cacert = /etc/openldap/certs/cacert.asc
ldap_search_base = dc=example,dc=com

3. Run a group lookup.
# getent group "Group R A"
Group R A:*:111000:
 
4. Try to expire the group record.
# sss_cache -E

5. Run ldbsearch and verify the dataExpireTimestamp in main sysdb (cache_LDAP.ldb).

# ldbsearch -H cache_LDAP.ldb -b "name=Group R A@ldap,cn=groups,cn=LDAP,cn=sysdb" | grep dataExpireTimestamp
asq: Unable to register control with rootdse!
dataExpireTimestamp: 1473107970

6. Run ldbsearch and verify the dataExpireTimestamp in time stamp cache.

# ldbsearch -H timestamps_LDAP.ldb -b "name=Group R A@ldap,cn=groups,cn=LDAP,cn=sysdb" | grep dataExpireTimestamp
dataExpireTimestamp: 1
 
Actual results:
dataExpireTimestamp in sysdb main cache is not set to 1 (or its not invalidated).

Expected results:
dataExpireTimestamp in sysdb main cache should be set to 1 for the group entries like other user entries in the cache.

Additional info: