[bugfix] make compile when DUNE_ISTL_WITH_CHECKING is defined.

(cherry picked from commit 396f32fb)

Signed-off-by: Christoph Grüninger <gruenich@dune-project.org>

dune/common/parallel/communicator.hh

@@ -1291,7 +1291,7 @@ namespace Dune
 
 
   template<class Data, class GatherScatter, bool FORWARD>
-  inline void BufferedCommunicator::MessageGatherer<Data,GatherScatter,FORWARD,SizeOne>::operator()(const InterfaceMap& interfaces, const Data& data, Type* buffer, size_t) const
+  inline void BufferedCommunicator::MessageGatherer<Data,GatherScatter,FORWARD,SizeOne>::operator()(const InterfaceMap& interfaces, const Data& data, Type* buffer, size_t bufferSize) const
   {
     typedef typename InterfaceMap::const_iterator
     const_iterator;