(finishing patch -- question was restored, but there were still problems)

Restore the wrap-around question when no more hits found while searching with Advanced Search.
The dispatched() flag is used currently in FindAndReplace.cpp in order to discriminate between
match found and not found and, in the latter case, pop-up the wrap-around question dialog.

git-svn-id: svn://svn.lyx.org/lyx/lyx-devel/trunk@36279 a592a061-630c-0410-9148-cb99ea01b6c8