As we are rolling out the user profile feature, we'd like to expand the [Usage API](https://www.elastic.co/guide/en/elasticsearch/reference/current/usage-api.html) to report usage stats of user profiles such as (1) number of enabled user profiles and (2) number of user profiles that are [activated](https://www.elastic.co/guide/en/elasticsearch/reference/current/security-api-activate-user-profile.html) over the past X days. 

Response of the Usage API already contains a `security` field that groups relevant stats from security related features. We expect the new stats for user profiles should be added under it as well, for example:
```
{
  "security: {
    "user_profile": {
      "activated": 78,
      "recently_activated": 42  <1>
    }
  }
}
```
<1> The use of `recently_` is chosen to avoid the field to be tied to a specific time period so it is easier to evolve the definition in future.

x-pack/plugin/security/src/main/java/org/elasticsearch/xpack/security/Security.java
private final boolean inFipsMode;
        ValidateLicenseForFIPS(boolean inFipsMode) {
            this.inFipsMode = inFipsMode;
        }
        @Override
        public void accept(DiscoveryNode node, ClusterState state) {
            if (inFipsMode) {
                License license = LicenseService.getLicense(state.metadata());
                if (license != null && XPackLicenseState.isFipsAllowedForOperationMode(license.operationMode()) == false) {
                    throw new IllegalStateException(
                        "FIPS mode cannot be used with a ["
                            + license.operationMode()
                            + "] license. It is only allowed with a Platinum or Trial license."
                    );
                }
            }
        }
    }
    @Override
    public void loadExtensions(ExtensionLoader loader) {
        securityExtensions.addAll(loader.loadExtensions(SecurityExtension.class));
    }