Make feedback table also store sender.

synapse/storage/feedback.py

@@ -28,6 +28,7 @@ class FeedbackStore(SQLBaseStore):
             "feedback_type": event.feedback_type,
             "room_id": event.room_id,
             "target_event_id": event.target_event,
+            "sender": event.user_id,
         })
 
     @defer.inlineCallback

synapse/storage/schema/im.sql

@@ -47,7 +47,8 @@ CREATE TABLE IF NOT EXISTS room_memberships(
 CREATE TABLE IF NOT EXISTS feedback(
     event_id TEXT NOT NULL,
     feedback_type TEXT,
-    target_event_id TEXT,sudo
+    target_event_id TEXT,
+    sender TEXT,
     room_id TEXT
 );