[dovecot/core] 481992: imap: Fix o_stream_is_corked() assert check

[GitHub]

  Branch: refs/heads/master
  Home:   https://github.com/dovecot/core
  Commit: 481992bfe2740bdec70fcd7366dea50ed9128966
      https://github.com/dovecot/core/commit/481992bfe2740bdec70fcd7366dea50ed9128966
  Author: Timo Sirainen <timo.sirainen at dovecot.fi>
  Date:   2017-12-13 (Wed, 13 Dec 2017)

  Changed paths:
    M src/imap/imap-client.c

  Log Message:
  -----------
  imap: Fix o_stream_is_corked() assert check

All the callers cork the stream, so this can only mean that the corking
failed because the connection was already closed. Continue handling the
input anyway.

Fixes:
Panic: file imap-client.c: line 1236 (client_handle_input): assertion failed: (o_stream_is_corked(client->output))