Use ClientProtectedResourceMixin from Core

(cherry picked from commit ca4d10b0)

aleksis/apps/resint/views.py

@@ -15,11 +15,12 @@ from django.views.generic.list import ListView
 
 from django_tables2 import SingleTableView
 from guardian.shortcuts import get_objects_for_user
-from oauth2_provider.views.mixins import ClientProtectedResourceMixin, ScopedResourceMixin
+from oauth2_provider.views.mixins import ScopedResourceMixin
 from reversion.views import RevisionMixin
 from rules.contrib.views import PermissionRequiredMixin
 
 from aleksis.core.mixins import AdvancedCreateView, AdvancedDeleteView, AdvancedEditView
+from aleksis.core.util.auth_helpers import ClientProtectedResourceMixin
 
 from .forms import PosterGroupForm, PosterUploadForm
 from .models import LiveDocument, Poster, PosterGroup