nsIImageFrame* imageFrame; GetImageFrame(&imageFrame);
if (!mCurrentRequest) { return NS_OK; }  nsCOMPtr<imgIContainer> image; mCurrentRequest->GetImage(getter_AddRefs(image)); if (!image) { return NS_OK; }
nsHTMLImageElement::GetNaturalHeight(PRInt32* aNaturalHeight){  NS_ENSURE_ARG_POINTER(aNaturalHeight);  *aNaturalHeight = 0;  nsIImageFrame* imageFrame;  GetImageFrame(&imageFrame);  if (!imageFrame)    return NS_OK; // don't throw JS exceptions in this case  PRUint32 width, height;  nsresult rv = imageFrame->GetNaturalImageSize(&width, &height);  if (NS_FAILED(rv))    return NS_OK;  *aNaturalHeight = (PRInt32)height;  return NS_OK;}