Return complete response from tenant_usages_client

Currently compute tenant_usages_client returns Response by
removing top key from Response.
For example-
 return service_client.ResponseBody(resp, body['tenant_usage'])

As service clients are in direction to move to Tempest-lib, all
service clients should return Response without any truncation.
One good example is Resource pagination links which are lost with current
way of return value. Resource pagination links are present in parallel
(not inside) to top key of Response.

This patch makes compute tenant_usages_client to return
complete Response body.

Change-Id: I0e6287b1a720d5f3f129fcaa8c08cf6d40abf8e8
Implements: blueprint method-return-value-and-move-service-clients-to-lib
diff --git a/tempest/api/compute/admin/test_simple_tenant_usage.py b/tempest/api/compute/admin/test_simple_tenant_usage.py
index 204281c..7333acb 100644
--- a/tempest/api/compute/admin/test_simple_tenant_usage.py
+++ b/tempest/api/compute/admin/test_simple_tenant_usage.py
@@ -50,14 +50,14 @@
     def test_list_usage_all_tenants(self):
         # Get usage for all tenants
         tenant_usage = self.adm_client.list_tenant_usages(
-            start=self.start, end=self.end, detailed="1")
+            start=self.start, end=self.end, detailed="1")['tenant_usages'][0]
         self.assertEqual(len(tenant_usage), 8)
 
     @test.idempotent_id('94135049-a4c5-4934-ad39-08fa7da4f22e')
     def test_get_usage_tenant(self):
         # Get usage for a specific tenant
         tenant_usage = self.adm_client.show_tenant_usage(
-            self.tenant_id, start=self.start, end=self.end)
+            self.tenant_id, start=self.start, end=self.end)['tenant_usage']
 
         self.assertEqual(len(tenant_usage), 8)
 
@@ -65,6 +65,6 @@
     def test_get_usage_tenant_with_non_admin_user(self):
         # Get usage for a specific tenant with non admin user
         tenant_usage = self.client.show_tenant_usage(
-            self.tenant_id, start=self.start, end=self.end)
+            self.tenant_id, start=self.start, end=self.end)['tenant_usage']
 
         self.assertEqual(len(tenant_usage), 8)
diff --git a/tempest/services/compute/json/tenant_usages_client.py b/tempest/services/compute/json/tenant_usages_client.py
index 72fcde2..73b4706 100644
--- a/tempest/services/compute/json/tenant_usages_client.py
+++ b/tempest/services/compute/json/tenant_usages_client.py
@@ -30,7 +30,7 @@
         resp, body = self.get(url)
         body = json.loads(body)
         self.validate_response(schema.list_tenant_usage, resp, body)
-        return service_client.ResponseBodyList(resp, body['tenant_usages'][0])
+        return service_client.ResponseBody(resp, body)
 
     def show_tenant_usage(self, tenant_id, **params):
         url = 'os-simple-tenant-usage/%s' % tenant_id
@@ -40,4 +40,4 @@
         resp, body = self.get(url)
         body = json.loads(body)
         self.validate_response(schema.get_tenant_usage, resp, body)
-        return service_client.ResponseBodyList(resp, body['tenant_usage'])
+        return service_client.ResponseBody(resp, body)