Include the correct header for std::lower_bound.

That is <algorithm>. Relying on indirect includes is bad, mmkay?

Change-Id: I245885672004cd406f98c82231aaa38a5cfe464c
Reviewed-by: Orgad Shaneh <orgads@gmail.com>
Reviewed-by: Erik Verbruggen <erik.verbruggen@digia.com>