Add Project User coverage for domain config API

This patch adds the test cases for project user coverage for
domain config API.

Subsequent patches will -

 - Removing obsolete policies in policy.v3cloudsample.json file

Change-Id: If6a5ccca76e378b10d4af6a5f46dbaaa23b290bc
Partial-Bug: #1805366

keystone/tests/unit/protection/v3/test_domain_config.py

@@ -591,3 +591,75 @@ class DomainUserTests(base_classes.TestCaseWithBootstrap,
             r = c.post('/v3/auth/tokens', json=auth)
             self.token_id = r.headers['X-Subject-Token']
             self.headers = {'X-Auth-Token': self.token_id}
+
+
+class ProjectUserTests(base_classes.TestCaseWithBootstrap,
+                       common_auth.AuthTestMixin,
+                       _SystemDomainAndProjectUserDomainConfigTests,
+                       _DomainAndProjectUserDomainConfigTests,
+                       _SystemReaderMemberDomainAndProjectUserDomainConfigTests):
+
+    def setUp(self):
+        super(ProjectUserTests, self).setUp()
+        self.loadapp()
+        self.useFixture(ksfixtures.Policy(self.config_fixture))
+        self.config_fixture.config(group='oslo_policy', enforce_scope=True)
+
+        self.user_id = self.bootstrapper.admin_user_id
+        auth = self.build_authentication_request(
+            user_id=self.user_id,
+            password=self.bootstrapper.admin_password,
+            project_id=self.bootstrapper.project_id
+        )
+
+        # Grab a token using the persona we're testing and prepare headers
+        # for requests we'll be making in the tests.
+        with self.test_client() as c:
+            r = c.post('/v3/auth/tokens', json=auth)
+            self.token_id = r.headers['X-Subject-Token']
+            self.headers = {'X-Auth-Token': self.token_id}
+
+
+class ProjectUserTestsWithoutEnforceScope(
+        base_classes.TestCaseWithBootstrap,
+        common_auth.AuthTestMixin,
+        _SystemDomainAndProjectUserDomainConfigTests,
+        _DomainAndProjectUserDomainConfigTests,
+        _SystemReaderMemberDomainAndProjectUserDomainConfigTests):
+
+    def setUp(self):
+        super(ProjectUserTestsWithoutEnforceScope, self).setUp()
+        self.loadapp()
+        self.useFixture(ksfixtures.Policy(self.config_fixture))
+
+        # Explicityly set enforce_scope to False to make sure we maintain
+        # backwards compatibility with project users.
+        self.config_fixture.config(group='oslo_policy', enforce_scope=False)
+
+        domain = PROVIDERS.resource_api.create_domain(
+            uuid.uuid4().hex, unit.new_domain_ref()
+        )
+        user = unit.new_user_ref(domain_id=domain['id'])
+        self.user_id = PROVIDERS.identity_api.create_user(user)['id']
+
+        self.project_id = PROVIDERS.resource_api.create_project(
+            uuid.uuid4().hex, unit.new_project_ref(domain_id=domain['id'])
+        )['id']
+
+        PROVIDERS.assignment_api.create_grant(
+            self.bootstrapper.member_role_id, user_id=self.user_id,
+            project_id=self.project_id
+        )
+
+        auth = self.build_authentication_request(
+            user_id=self.user_id,
+            password=user['password'],
+            project_id=self.project_id
+        )
+
+        # Grab a token using the persona we're testing and prepare headers
+        # for requests we'll be making in the tests.
+        with self.test_client() as c:
+            r = c.post('/v3/auth/tokens', json=auth)
+            self.token_id = r.headers['X-Subject-Token']
+            self.headers = {'X-Auth-Token': self.token_id}