if (!aFlagsToUpdate && !aScriptLevelIncrement) return NS_OK;
  UpdatePresentationDataFromChildAt(nsIPresContext* aPresContext,                                    PRInt32         aFirstIndex,                                    PRInt32         aLastIndex,                                    PRInt32         aScriptLevelIncrement,                                    PRUint32        aFlagsValues,                                    PRUint32        aFlagsToUpdate)  {    PRInt32 index = 0;    nsIFrame* childFrame = mFrames.FirstChild();    while (childFrame) {      if ((index >= aFirstIndex) &&          ((aLastIndex <= 0) || ((aLastIndex > 0) && (index <= aLastIndex)))) {        PropagatePresentationDataFor(aPresContext, childFrame,          aScriptLevelIncrement, aFlagsValues, aFlagsToUpdate);      }      index++;      childFrame->GetNextSibling(&childFrame);    }    return NS_OK;  }