bug#25561: 25.1; "Making isearch-search-fun-function local to *Minibuf-1* while let-bound!" warning with Evil

[Vasilij Schneidermann <v.schneidermann@gmail.com>]

Hello,

a user of the Evil package reported [1] that using a search command
results in a "Making isearch-search-fun-function local to *Minibuf-1*
while let-bound!" warning.  This appears to be an interaction between
isearch and Evil, more specifically, Evil let-binds
`isearch-search-fun-function' to something of its own, invokes isearch
and something in isearch ends up running
`minibuffer-history-isearch-setup' which `make-local-variable' to have
`isearch-search-fun-function' have a separate value, resulting in the
aforementioned warning.

What's the recommended way to avoid or silence it?  Stefan suggested
elsewhere [2] that this might indicate a bug, hence why I'm bringing
this up here.

[1]: https://github.com/emacs-evil/evil/issues/748
[2]: https://lists.gnu.org/archive/html/emacs-devel/2010-06/msg00903.html