Get rid of include directives inside namespace blocks (bug #339).

Eigen/src/SparseCore/SparseRedux.h

@@ -25,6 +25,8 @@
 #ifndef EIGEN_SPARSEREDUX_H
 #define EIGEN_SPARSEREDUX_H
 
+namespace Eigen { 
+
 template<typename Derived>
 typename internal::traits<Derived>::Scalar
 SparseMatrixBase<Derived>::sum() const
@@ -53,4 +55,6 @@ SparseVector<_Scalar,_Options,_Index>::sum() const
   return Matrix<Scalar,1,Dynamic>::Map(&m_data.value(0), m_data.size()).sum();
 }
 
+} // end namespace Eigen
+
 #endif // EIGEN_SPARSEREDUX_H