npostavs@users.sourceforge.net writes:

> (Info-select-node, Info-search): Replace (signal 'search-failed ...)
> with (user-error "Search failed: "...).

Turns out this breaks isearch over multiple nodes, as noted by Mark
Oteiza in [1].  I believe this is fixed by the patch below.

[1]: http://lists.gnu.org/archive/html/emacs-devel/2017-03/msg00869.html