This is for consistency with the rest of our code dealing with message
delivery, which always uses the user_profile_id.
(imported from commit 5bf10bb9b994b0a98d3a22bd0bd86e542ab8a2ee)
Previously, if last was None, we wouldn't check dont_block,
server_generation, or any of the other reasons that get_updates might
return immediately, and just unconditionally entered longpolling mode.
In the process, this reorders return_messages_immediately to have
fewer cases and thus be easier to read.
(imported from commit 67803b8bfc7d9c9c1a4d6916eb2fb62664fb35a9)
This check was a workaround for the fact that the browser client
submitted a "last" value of -1.
(imported from commit a668f6a4e7a0c027f1214166a9bbf40d29b5daeb)
We shouldn't deploy this change until strictly after we deploy
"Fix website improperly submitting a last value of -1."
or we will break website clients.
(imported from commit 7f682ab0f7060b677f53f0a0073faef216f45d00)
Tim Abbott