Adding tenant_id to policy default

The policy engine already automatically sets the target project_id
some policy files use tenant_id instead. See recent neutron policy
file. Also adding tenant_id to the credential list that is
populated.

Why this matters is that batch actions don't have data associated
with them when the policy checks are made so policy files that
use tenant_id instead of project_id will fail.

Closes-Bug: #1598242
Change-Id: I1b7c5c545852e76cbd46ece003ee9bbb0c19fdec

openstack_auth/policy.py

@@ -121,6 +121,8 @@ def check(actions, request, target=None):
     # the service APIs will correct us if we are too permissive.
     if target.get('project_id') is None:
         target['project_id'] = user.project_id
+    if target.get('tenant_id') is None:
+        target['tenant_id'] = target['project_id']
     # same for user_id
     if target.get('user_id') is None:
         target['user_id'] = user.id
@@ -187,6 +189,7 @@ def _user_to_credentials(user):
                              'token': user.token,
                              'username': user.username,
                              'project_id': user.project_id,
+                             'tenant_id': user.project_id,
                              'project_name': user.project_name,
                              'domain_id': user.user_domain_id,
                              'is_admin': user.is_superuser,