anchor.diff:  
     void _processHits(List scriptHits) {
       // Update hits table.
  -    _hits.clear();
       for (var i = 0; i < scriptHits.length; i += 2) {
         var line = scriptHits[i];
         var hit = scriptHits[i + 1]; // hit status.
         assert(line >= 1); // Lines start at 1.
  +      var oldHits = _hits[line];
  +      if (oldHits != null) {
  +        hit += oldHits;
  +      }
         _hits[line] = hit;
       }
       _applyHitsToLines();
  
positive.code:     }
      children.add(cls);
    }
    
    Future<ServiceObject> get(String command) {
      return isolate.get(id + "/$command");
    }
  
negative.code:       superClass._addToChildren(this);
      }
      error = map['error'];
  
      var allocationStats = map['allocationStats'];
      if (allocationStats != null) {
        newSpace.update(allocationStats['new']);
  