this changes the behavior when scanning a setup-contact qr-code.
instead of waiting, until the whole protocol is finished,
which may take something between 10 seconds and several minutes,
the dc_join_secure_join() returns instantly;
the uis typically show the created chat then.
the returned chat-id is the same than if we wait for the protocol to finish,
it is the opportunistic one-to-one chat-id, so no changes there.
all this works even when both devices are offline.
after dc_join_secure_join() returns, however,
the usual setup-contact continues. ux-wise, once the protocol finishes,
a system-info-messages is added to the chat (also unchanged),
this is directly visible, in the chat as well as in the chatlist.
while the prococol runs, the user can alredy send message to the chat,
or do other things in the app.
if the user scans a new qr-code while an existing protocol is not finished yet,
the old join will be aborted (however, of course, created chats are kept).
we could also allow multiple joins at the same time,
however, this would be much more effort that this little change
and i am not sure if it is worth the effort.
finally, if a verified-group shall be joined,
this is not possible instantly, this is not affected by this pr.
same for unverified-groups, however, this could maybe be improved,
but also here, not sure if it is worth the effort
(i think most scans are setup-contact scans)
oauth2 crashes in beta23
because we did not let Serde remove the quotes from a parsed JSON email-address.
for autoconfig, we try to get a well-known URL
containing the domain of the used address - with the quote that is
https://autoconfig.gmail.com"/mail/config-v1.1.xml?...
unfortunately, instead of just returning an error,
(the url does not exist anyway)
reqwest crashes on the attempt to get this URL.
the Serde-thing is not obvious to me:
while serde_json::Value.as_str() removes the quotes,
serde_json::Value.to_string() does not.
.truncate() is not safe because it panics if string length does not
lie on character boundary. We convert the string to characters and take
first n character instead.
