* Apply code corrections for the new layer types.
* Support not passing `user` to `get_permissions`.
* `download_profile_photo` now supports `MessageService`.
* `thumb` in send and edit message.
* Document new known errors.
Fixes#1426. Not entirely happy with the new indirection layer,
but the original __call__ method is already a mess anyway and
the additional cost of an extra call should be neglible compared
to the actual IO.
Only the uses of `isinstance` against `InputPeer*` types were
reviewed. Notably, `utils` is exempt on this because it needs
to deal with everything on a case-by-case basis.
Since the addition of `*FromMessage` peers, any manual `isinstance`
checks to determine the type were prone to breaking or being
forgotten to be updated, so a common `helpers._entity_type()`
method was made to share this logic.
Since the conversion to `Peer` would be too expensive, a simpler
check against the name is made, which should be fast and cheap.
First of all, because it shouldn't be doing that. Second, it was
buggy and was passing the tuple returned by get_input_location to
download_file which doesn't accept tuples (instead it should be
passed the photo object so that download_file could return dc_id
and input file location itself).
It's the only way to properly clean all background tasks,
which the library makes heavy use for in MTProto/Connection
send and receive loops.
Some parts of the code even relied on the fact that it was
asynchronous (it used to return a future so you could await
it and not be breaking).
It's automatically syncified to reduce the damage of being
a breaking change.
These two occur when replying to an inline query with a photo and
InputBotInlineMessageMediaAuto empty message, and passing URLs to
PNGs that may not be accessible (i.e. 403 from pixiv).
