mBullet = nsnull;
nsBlockFrame::DeleteFrame(nsIPresContext& aPresContext){  // Outside bullets are not in our child-list so check for them here  // and delete them when present.  if (HaveOutsideBullet()) {    mBullet->DeleteFrame(aPresContext);    mBullet = nsnull;  }  nsLineBox::DeleteLineList(aPresContext, mLines);  nsLineBox::DeleteLineList(aPresContext, mOverflowLines);  mFloaters.DeleteFrames(aPresContext);  return nsBlockFrameSuper::DeleteFrame(aPresContext);}