optimized assignment operator for FieldVector<1>

[[Imported from SVN: r6272]]

dune/common/fvector.hh

@@ -151,7 +151,12 @@ namespace Dune {
     /** \brief Constructor with a given scalar */
     FieldVector (const K& k) : _data(k) {}
 
-    using Base::operator=;
+    //! Assignment operator for scalar
+    inline FieldVector& operator= (const K& k)
+    {
+      _data = k;
+      return *this;
+    }
 
     //===== forward methods to container
     size_type vec_size() const { return 1; }