firstInFlow->GetPrevInFlow(&previous);
previous = firstInFlow->GetPrevInFlow();
nsContinuingTextFrame::GetFirstInFlow() const{  // Can't cast to |nsContinuingTextFrame*| because the first one isn't.  nsIFrame *firstInFlow,           *previous = NS_CONST_CAST(nsIFrame*,                                     NS_STATIC_CAST(const nsIFrame*, this));  do {    firstInFlow = previous;    firstInFlow->GetPrevInFlow(&previous);  } while (previous);  return firstInFlow;}