require secondary template parameter for findLower
findLower has typename ListType::const_reference val for its value parameter, which limits the type of comparison predicate.
Change needed for #801 (closed) to use for a binary search on a PtrList of XXX. For example,
const polyPatchList& patches = *this;
return
findLower
(
patches,
faceIndex,
0,
[](const polyPatch& p, label val) { return (p.start() <= val); }
);