httpclient: Fix cancellation
httpclient: Fix cancellation

Free the CheckData in an idle handler because soup_session_abort
invokes http_client_check_response_cb. Trying to disconnect the
GCancellable from a 'cancelled' signal handler will result in a
deadlock.

Fixes: https://bugzilla.gnome.org/689642

felipeborges/gnome-online-accounts,ritzk/gnome-online-accounts,ritzk/gnome-online-accounts,halfline/gnome-online-accounts,dnohales/gnome-online-accounts,dnohales/gnome-online-accounts,Distrotech/gnome-online-accounts,halfline/gnome-online-accounts,ritzk/gnome-online-accounts,Distrotech/gnome-online-accounts,halfline/gnome-online-accounts,dnohales/gnome-online-accounts,felipeborges/gnome-online-accounts,felipeborges/gnome-online-accounts,Distrotech/gnome-online-accounts