More bug fixes related to grouped dimension handling.

sc/source/core/data/dpobject.cxx

@@ -564,6 +564,9 @@ void ScDPObject::ReloadGroupTableData()
         // No dimension data. Most likey it doesn't have any group dimensions.
         return;
 
+    if (!mpTableData)
+        return;
+
     ScDPGroupTableData* pData = dynamic_cast<ScDPGroupTableData*>(mpTableData.get());
     if (pData)
     {

sc/source/ui/docshell/dbdocfun.cxx

@@ -1328,7 +1328,7 @@ bool ScDBDocFunc::DataPilotUpdate( ScDPObject* pOldObj, const ScDPObject* pNewOb
                     pDestObj->ClearTableData();
 
                 if (pDestObj->HasGroups())
-                    pDestObj->ClearTableData();
+                    pDestObj->ReloadGroupTableData();
 
                 pDestObj->InvalidateData();             // before getting the new output area