stop using g.user in Follower.fetch_page

for #690

models.py

@@ -1048,14 +1048,15 @@ class Follower(ndb.Model):
         return follower
 
     @staticmethod
-    def fetch_page(collection):
-        """Fetches a page of Followers for the current user.
+    def fetch_page(collection, user):
+        """Fetches a page of :class:`Follower`s for a given user.
 
         Wraps :func:`fetch_page`. Paging uses the ``before`` and ``after`` query
         parameters, if available in the request.
 
         Args:
           collection (str): ``followers`` or ``following``
+          user (User)
 
         Returns:
           (list of Follower, str, str) tuple: results, annotated with an extra
@@ -1068,7 +1069,7 @@ class Follower(ndb.Model):
         filter_prop = Follower.to if collection == 'followers' else Follower.from_
         query = Follower.query(
             Follower.status == 'active',
-            filter_prop == g.user.key,
+            filter_prop == user.key,
         ).order(-Follower.updated)
 
         followers, before, after = fetch_page(query, Follower, by=Follower.updated)

pages.py

@@ -53,6 +53,9 @@ def load_user(protocol, id):
       protocol (str):
       id (str):
 
+    Returns:
+      models.User:
+
     Raises:
       :class:`werkzeug.exceptions.HTTPException` on error or redirect
     """
@@ -85,6 +88,7 @@ def load_user(protocol, id):
         error(f'{protocol} user {id} not found', status=404)
 
     assert not g.user.use_instead
+    return g.user
 
 
 @app.route('/')
@@ -158,9 +162,9 @@ def notifications(protocol, id):
 @app.get(f'/<any({",".join(PROTOCOLS)}):protocol>/<id>/<any(followers,following):collection>')
 @canonicalize_request_domain(common.PROTOCOL_DOMAINS, common.PRIMARY_DOMAIN)
 def followers_or_following(protocol, id, collection):
-    load_user(protocol, id)
+    user = load_user(protocol, id)
 
-    followers, before, after = Follower.fetch_page(collection)
+    followers, before, after = Follower.fetch_page(collection, user)
     num_followers, num_following = g.user.count_followers()
     return render_template(
         f'{collection}.html',