Fix bug about snapshot pagination

Now, one page content will be changed after Clicking
"Next page" or "Prev page" to go back.

As we know, the order of the list could not be changed
at will, for one at the beginning or the end is a marker.
The marker is very importent for pagination.
So, this commit remove the sort of snapshots and reverse
the sort of the previous page ones.

Change-Id: I8d3d0cf4a1e6526bed3055b18741b1cf5d6166ff
Closes-Bug: #1804391

openstack_dashboard/api/cinder.py

@@ -296,6 +296,9 @@ def update_pagination(entities, page_size, marker, sort_dir):
     elif marker is not None:
         has_prev_data = True
 
+    if sort_dir == 'asc':
+        entities.reverse()
+
     return entities, has_more_data, has_prev_data
 
 

openstack_dashboard/dashboards/admin/snapshots/views.py

@@ -75,8 +75,7 @@ class SnapshotsView(tables.PagedTableMixin, tables.DataTableView):
 
         else:
             snapshots = []
-        return sorted(snapshots,
-                      key=lambda snapshot: snapshot.tenant_name or '')
+        return snapshots
 
 
 class UpdateStatusView(forms.ModalFormView):

openstack_dashboard/dashboards/project/volumes/views.py

@@ -62,10 +62,6 @@ class VolumeTableMixIn(object):
                 cinder.volume_list_paged(self.request, marker=marker,
                                          search_opts=search_opts,
                                          sort_dir=sort_dir, paginate=True)
-
-            if sort_dir == "asc":
-                volumes.reverse()
-
             return volumes
         except Exception:
             exceptions.handle(self.request,