create-channel: Rename send_messages_for_new_subscribers helper.

Because send_messages_for_new_subscribers also sends channel
notification messages about newly created channels, a clearer
name for is send_user_subscribed_and_new_channel_notifications.

(cherry picked from commit 8b1e536e6b)

zerver/tests/test_subs.py

@@ -4416,7 +4416,7 @@ class SubscriptionAPITest(ZulipTestCase):
         with (
             self.assert_database_query_count(23),
             self.assert_memcached_count(11),
-            mock.patch("zerver.views.streams.send_messages_for_new_subscribers"),
+            mock.patch("zerver.views.streams.send_user_subscribed_and_new_channel_notifications"),
         ):
             self.subscribe_via_post(
                 desdemona,

zerver/views/streams.py

@@ -829,7 +829,7 @@ def create_channel(
         send_new_subscription_messages
         and len(new_subscribers) <= settings.MAX_BULK_NEW_SUBSCRIPTION_MESSAGES
     ):
-        send_messages_for_new_subscribers(
+        send_user_subscribed_and_new_channel_notifications(
             user_profile=user_profile,
             subscribers=new_subscribers,
             new_subscriptions={str(user.id): [name] for user in new_subscribers},
@@ -1017,7 +1017,7 @@ def add_subscriptions_backend(
 
     if send_new_subscription_messages:
         if len(result["subscribed"]) <= settings.MAX_BULK_NEW_SUBSCRIPTION_MESSAGES:
-            send_messages_for_new_subscribers(
+            send_user_subscribed_and_new_channel_notifications(
                 user_profile=user_profile,
                 subscribers=subscribers,
                 new_subscriptions=result["subscribed"],
@@ -1036,7 +1036,7 @@ def add_subscriptions_backend(
     return json_success(request, data=result)
 
 
-def send_messages_for_new_subscribers(
+def send_user_subscribed_and_new_channel_notifications(
     user_profile: UserProfile,
     subscribers: set[UserProfile],
     new_subscriptions: dict[str, list[str]],