Remove two checks from rotation.h

This allows rotation.h to remove its dependency on glog.

Change-Id: Ia6aede93ee51a4bd4039570dc8edd100a7045329
diff --git a/include/ceres/rotation.h b/include/ceres/rotation.h
index e9496d7..b6a06f7 100644
--- a/include/ceres/rotation.h
+++ b/include/ceres/rotation.h
@@ -48,7 +48,6 @@
 #include <algorithm>
 #include <cmath>
 #include <limits>
-#include "glog/logging.h"
 
 namespace ceres {
 
@@ -418,7 +417,6 @@
 inline void EulerAnglesToRotationMatrix(const T* euler,
                                         const int row_stride_parameter,
                                         T* R) {
-  CHECK_EQ(row_stride_parameter, 3);
   EulerAnglesToRotationMatrix(euler, RowMajorAdapter3x3(R));
 }
 
@@ -496,7 +494,6 @@
   QuaternionToScaledRotation(q, R);
 
   T normalizer = q[0]*q[0] + q[1]*q[1] + q[2]*q[2] + q[3]*q[3];
-  CHECK_NE(normalizer, T(0));
   normalizer = T(1) / normalizer;
 
   for (int i = 0; i < 3; ++i) {