Tags: patch

This fixes an issue in `tex-recenter-output-buffer` (which affect
several other commands that rely on it) where it calls `display-buffer`
and tries to select the returned window, without checking that
`display-buffer` returned non-nil.  This leads to an error when
`display-tex-shell-buffer-action` or `display-buffer-alist` are
configured to prevent the display of the *tex-shell* buffer.