ClangTidy fixes

Change-Id: I1bccb4ea27a9010e869265436c8bfbcb72fb1484

internal/ceres/fake_bundle_adjustment_jacobian.cc

diff --git a/internal/ceres/fake_bundle_adjustment_jacobian.cc b/internal/ceres/fake_bundle_adjustment_jacobian.cc
index dd2aee8..af1d03c 100644
--- a/internal/ceres/fake_bundle_adjustment_jacobian.cc
+++ b/internal/ceres/fake_bundle_adjustment_jacobian.cc
@@ -30,10 +30,10 @@
 
 #include "ceres/fake_bundle_adjustment_jacobian.h"
 
-#include <iostream>
 #include <memory>
 #include <random>
 #include <string>
+#include <utility>
 
 #include "Eigen/Dense"
 #include "ceres/block_sparse_matrix.h"

internal/ceres/power_series_expansion_preconditioner_test.cc

diff --git a/internal/ceres/power_series_expansion_preconditioner_test.cc b/internal/ceres/power_series_expansion_preconditioner_test.cc
index 233d4f7..fd1ab4b 100644
--- a/internal/ceres/power_series_expansion_preconditioner_test.cc
+++ b/internal/ceres/power_series_expansion_preconditioner_test.cc
@@ -30,6 +30,8 @@
 
 #include "ceres/power_series_expansion_preconditioner.h"
 
+#include <memory>
+
 #include "Eigen/Dense"
 #include "ceres/linear_least_squares_problems.h"
 #include "gtest/gtest.h"