LinearSolver::Options::num_eliminate_blocks is dead.

Replaced with LinearSolver::Options::elimination_groups.

Change-Id: I7c07542ec19279a35ddf6da498d417a79395c77f
diff --git a/internal/ceres/iterative_schur_complement_solver.cc b/internal/ceres/iterative_schur_complement_solver.cc
index 679c41f..376a586 100644
--- a/internal/ceres/iterative_schur_complement_solver.cc
+++ b/internal/ceres/iterative_schur_complement_solver.cc
@@ -67,7 +67,7 @@
   // Initialize a ImplicitSchurComplement object.
   if (schur_complement_ == NULL) {
     schur_complement_.reset(
-        new ImplicitSchurComplement(options_.num_eliminate_blocks,
+        new ImplicitSchurComplement(options_.elimination_groups[0],
                                     options_.preconditioner_type == JACOBI));
   }
   schur_complement_->Init(*A, per_solve_options.D, b);