Fix some looping_call calls which were broken in #3604

It turns out that looping_call does check the deferred returned by its
callback, and (at least in the case of client_ips), we were relying on this,
and I broke it in #3604.

Update run_as_background_process to return the deferred, and make sure we
return it to clock.looping_call.

1 files changed, 2 insertions, 2 deletions

diff --git a/synapse/app/homeserver.py b/synapse/app/homeserver.py

index b7e7718290..57b815d777 100755
--- a/synapse/app/homeserver.py
+++ b/synapse/app/homeserver.py
@@ -429,7 +429,7 @@ def run(hs):
     stats_process = []
 
     def start_phone_stats_home():
-        run_as_background_process("phone_stats_home", phone_stats_home)
+        return run_as_background_process("phone_stats_home", phone_stats_home)
 
     @defer.inlineCallbacks
     def phone_stats_home():
@@ -502,7 +502,7 @@ def run(hs):
             )
 
     def generate_user_daily_visit_stats():
-        run_as_background_process(
+        return run_as_background_process(
             "generate_user_daily_visits",
             hs.get_datastore().generate_user_daily_visits,
         )