When changing focus away and back to vim while in the middle of editing
the command-line, vim-tmux-focus-events emits errors from the function
called by the `:cnoremap` mappings. This patch replaces these mappings
with a call to `do#sink()` which does nothing. Simply removing the
mappings will result in `<F24><F25>` being inserted on the command-line
since tmux will send this text when `tmux set-option -g focus-events
on`, this is why `do#sink()` is needed.
Kenneth Benzie (Benie)
92a23103e3