[libsoup] Non-fast-forward update to branch return-if-client_io-is-null

[Diego Pino <dpino src gnome org>]

The branch 'return-if-client_io-is-null' was changed in a way that was not a fast-forward update.
NOTE: This may cause problems for people pulling from the branch. For more information,
please see:

 https://wiki.gnome.org/Git/Help/NonFastForward

Commits removed from the branch:

  303b671... Disconnect signal handlers in 'soup_client_message_io_http1
  1d513e3... Disconnect handler 'request_body_stream_wrote_data_cb' in '

Commits added to the branch:

  a51946d... Refactor common code in 'soup_client_message_io_http1_finis