Loosen tolerances in dense_qr_test.cc

Change-Id: I97f093f5f374465ca40d2a1a774373a3718e3302

internal/ceres/dense_qr_test.cc

diff --git a/internal/ceres/dense_qr_test.cc b/internal/ceres/dense_qr_test.cc
index c71f40e..b33de35 100644
--- a/internal/ceres/dense_qr_test.cc
+++ b/internal/ceres/dense_qr_test.cc
@@ -90,7 +90,7 @@
         EXPECT_EQ(summary.termination_type, LINEAR_SOLVER_SUCCESS);
         EXPECT_NEAR((x - actual).norm() / x.norm(),
                     0.0,
-                    std::numeric_limits<double>::epsilon() * 100)
+                    std::numeric_limits<double>::epsilon() * 400)
             << "\nexpected: " << x.transpose()
             << "\nactual  : " << actual.transpose();
       }