oqgraph: remove redundant update_virtual_fields() calls

storage/oqgraph/oqgraph_thunk.cc

@@ -193,9 +193,6 @@ int oqgraph3::cursor::restore_position()
       return rc;
     }
 
-    if (table.vfield)
-      table.update_virtual_fields(VCOL_UPDATE_FOR_READ);
-
     table.file->position(table.record[0]);
 
     while (memcmp(table.file->ref, _position.data(), table.file->ref_length))
@@ -206,9 +203,6 @@ int oqgraph3::cursor::restore_position()
         return rc;
       }
 
-      if (table.vfield)
-        table.update_virtual_fields(VCOL_UPDATE_FOR_READ);
-
       if ((_origid && vertex_id(_graph->_source->val_int()) != *_origid) ||
           (_destid && vertex_id(_graph->_target->val_int()) != *_destid))
       {
@@ -230,9 +224,6 @@ int oqgraph3::cursor::restore_position()
       table.file->ha_rnd_end();
       return rc;
     }
-
-    if (table.vfield)
-      table.update_virtual_fields(VCOL_UPDATE_FOR_READ);
   }
 
   _graph->_cursor= this;
@@ -310,8 +301,6 @@ int oqgraph3::cursor::seek_next()
     return clear_position(rc);
   }
 
-  if (table.vfield)
-    table.update_virtual_fields(VCOL_UPDATE_FOR_READ);
   _graph->_stale= true;
 
   if ((_origid && vertex_id(_graph->_source->val_int()) != *_origid) ||
@@ -345,8 +334,6 @@ int oqgraph3::cursor::seek_prev()
     return clear_position(rc);
   }
 
-  if (table.vfield)
-    table.update_virtual_fields(VCOL_UPDATE_FOR_READ);
   _graph->_stale= true;
 
   if ((_origid && vertex_id(_graph->_source->val_int()) != *_origid) ||
@@ -507,9 +494,6 @@ int oqgraph3::cursor::seek_to(
       return clear_position(rc);
     }
 
-    if (table.vfield)
-      table.update_virtual_fields(VCOL_UPDATE_FOR_READ);
-
     if ((_origid && vertex_id(_graph->_source->val_int()) != *_origid) ||
         (_destid && vertex_id(_graph->_target->val_int()) != *_destid))
     {