Reviewed as https://reviews.llvm.org/D41748
* These tests use function objects from functional, back_inserter from iterator, and equal from algorithm, so add those headers.
* The use of iota targeting vector<unsigned char> with an int parameter triggers warnings on MSVC++ assigning an into a unsigned char&; so change the parameter to unsigned char with a static_cast.
* Avoid naming unary_function in identity here as that is removed in '17. (This also fixes naming _VSTD, _NOEXCEPT_, and other libcxx-isms)
* Change the predicate in the transform tests to add_ten so that problems with multiple application are caught.
git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@321922 91177308-0d34-0410-b5e6-96231b3b80d8
