modules/federation: Return the response x val rather than default construction in handlers.

modules/federation/backfill.cc

@@ -127,7 +127,7 @@ get__backfill(client &client,
 		pdus.append(event);
 	}
 
-	return {};
+	return response;
 }
 
 static size_t

modules/federation/backfill_ids.cc

@@ -128,7 +128,7 @@ get__backfill_ids(client &client,
 		pdus.append(event_id);
 	}
 
-	return {};
+	return response;
 }
 
 resource::method

modules/federation/event.cc

@@ -72,7 +72,7 @@ handle_get(client &client,
 	};
 
 	pdus.append(event);
-	return {};
+	return response;
 }
 
 resource::method method_get

modules/federation/event_auth.cc

@@ -99,7 +99,7 @@ get__event_auth(client &client,
 			auth_chain.append(event);
 	});
 
-	return {};
+	return response;
 }
 
 resource::method

modules/federation/send_join.cc

@@ -181,7 +181,7 @@ put__send_join(client &client,
 		});
 	}
 
-	return {};
+	return response;
 }
 
 resource::method

modules/federation/state.cc

@@ -117,7 +117,7 @@ get__state(client &client,
 		});
 	}
 
-	return {};
+	return response;
 }
 
 resource::method

modules/federation/state_ids.cc

@@ -112,7 +112,7 @@ get__state_ids(client &client,
 		});
 	}
 
-	return {};
+	return response;
 }
 
 resource::method

modules/federation/user_devices.cc

@@ -120,5 +120,5 @@ get__user_devices(client &client,
 		return true;
 	});
 
-	return {};
+	return response;
 }