C++17 removes random_shuffle breaks ceres-solver

[NeroBurner]

Ceres-Solver with C++17 won't compile.

C++14 deprecates random_shuffle, C++17 removes random_shuffle
As replacement since C++11 std::shuffle is provided
Source: http://en.cppreference.com/w/cpp/algorithm/random_shuffle

In current master only schur_eliminator_impl.h seems to use random_shuffle

ceres-solver/internal/ceres/schur_eliminator_impl.h

Line 155 in 5d8b494

random_shuffle(chunks_.begin(), chunks_.end());

Since 282b8b5 ceres-solver requires at least C++11. Therefore this change should make no problems

CC: @norbertwenzel

[sandwichmaker]

@NeroBurner that line can likely just be dropped. Please feel free to send a CL.

[norbertwenzel]

@sandwichmaker you mean removing the chunk shuffling altogether or just replacing it with C++11's std::shuffle() with a proper random number generator?