Replace scoped_ptr with C++11's unique_ptr

Change-Id: Ib5a504c491e3a79af52a95accf009df473470c6b
diff --git a/internal/ceres/block_random_access_diagonal_matrix.cc b/internal/ceres/block_random_access_diagonal_matrix.cc
index 052690d..9866e75 100644
--- a/internal/ceres/block_random_access_diagonal_matrix.cc
+++ b/internal/ceres/block_random_access_diagonal_matrix.cc
@@ -34,9 +34,9 @@
 #include <set>
 #include <utility>
 #include <vector>
+
 #include "Eigen/Dense"
 #include "ceres/internal/port.h"
-#include "ceres/internal/scoped_ptr.h"
 #include "ceres/stl_util.h"
 #include "ceres/triplet_sparse_matrix.h"
 #include "ceres/types.h"