Clean up [identity-feature-enable] options for old releases

Project tags API and application credentials API are default features
since Queens and we can now assume these features are available when
identity v3 API is available. Becuase queens and older releases are no
longer supported by tempest, we can drop the options to enable tests
for these features.

Also, access rules for application credentials has been a default
feature since train so we can also assume this feature is available,
because train and older releases are no longer supported.

Change-Id: I138ac02f61c5a0a22ce0d5ad2d600a09166a4764
diff --git a/releasenotes/notes/identity-feature-opt-cleanup-caracal-7afd283855a07025.yaml b/releasenotes/notes/identity-feature-opt-cleanup-caracal-7afd283855a07025.yaml
new file mode 100644
index 0000000..67f6ede
--- /dev/null
+++ b/releasenotes/notes/identity-feature-opt-cleanup-caracal-7afd283855a07025.yaml
@@ -0,0 +1,21 @@
+---
+upgrade:
+  - |
+    The following deprecated options in the ``[identity-feature-enabled]``
+    section have been removed. Project tags API and application credentials
+    API are now always tested if identity v3 API is available.
+
+    - ``project_tag``
+    - ``application_credentials``
+
+  - |
+    Default value of the ``[identity-feature-enabled] access_rule`` option has
+    been changed from ``False`` to ``True`` and now the access rule API is
+    always tested when identity API is available.
+
+deprecations:
+  - |
+    The Keystone access_rule is enabled by default since Train release and we
+    no longer need a separate config in Tempest to enable it. Therefore
+    the ``[identity-feature-enabled] access_rule`` option has been deprecated
+    and will be removed in a future release.
diff --git a/tempest/api/identity/admin/v3/test_project_tags.py b/tempest/api/identity/admin/v3/test_project_tags.py
index 2cc7257..2004cbc 100644
--- a/tempest/api/identity/admin/v3/test_project_tags.py
+++ b/tempest/api/identity/admin/v3/test_project_tags.py
@@ -13,8 +13,6 @@
 #    License for the specific language governing permissions and limitations
 #    under the License.
 
-import testtools
-
 from tempest.api.identity import base
 from tempest import config
 from tempest.lib.common.utils import data_utils
@@ -33,8 +31,6 @@
     force_tenant_isolation = False
 
     @decorators.idempotent_id('7c123aac-999d-416a-a0fb-84b915ab10de')
-    @testtools.skipUnless(CONF.identity_feature_enabled.project_tags,
-                          'Project tags not available.')
     def test_list_update_delete_project_tags(self):
         """Test listing, updating and deleting of project tags"""
         project = self.setup_test_project()
diff --git a/tempest/api/identity/base.py b/tempest/api/identity/base.py
index c9e0e1c..9cdd917 100644
--- a/tempest/api/identity/base.py
+++ b/tempest/api/identity/base.py
@@ -322,13 +322,6 @@
 class BaseApplicationCredentialsV3Test(BaseIdentityV3Test):
 
     @classmethod
-    def skip_checks(cls):
-        super(BaseApplicationCredentialsV3Test, cls).skip_checks()
-        if not CONF.identity_feature_enabled.application_credentials:
-            raise cls.skipException("Application credentials are not available"
-                                    " in this environment")
-
-    @classmethod
     def resource_setup(cls):
         super(BaseApplicationCredentialsV3Test, cls).resource_setup()
         cls.user_id = cls.os_primary.credentials.user_id
diff --git a/tempest/config.py b/tempest/config.py
index 893148b..093b0b6 100644
--- a/tempest/config.py
+++ b/tempest/config.py
@@ -263,23 +263,11 @@
                 default=False,
                 help='Does the environment have the security compliance '
                      'settings enabled?'),
-    cfg.BoolOpt('project_tags',
-                default=True,
-                help='Is the project tags identity v3 API available?',
-                deprecated_for_removal=True,
-                deprecated_reason='Project tags API is a default feature '
-                                  'since Queens'),
-    cfg.BoolOpt('application_credentials',
-                default=True,
-                help='Does the environment have application credentials '
-                     'enabled?',
-                deprecated_for_removal=True,
-                deprecated_reason='Application credentials is a default '
-                                  'feature since Queens'),
-    # Access rules for application credentials is a default feature in Train.
-    # This config option can removed once Stein is EOL.
     cfg.BoolOpt('access_rules',
-                default=False,
+                default=True,
+                deprecated_for_removal=True,
+                deprecated_reason='Access rules for application credentials '
+                                  'is a default feature since Train',
                 help='Does the environment have access rules enabled?'),
     cfg.BoolOpt('immutable_user_source',
                 default=False,