mDisabled = ((PR_TRUE == aEnabled) ? PR_FALSE : PR_TRUE);
mDisabled = !aEnabled;
CSSStyleSheetImpl::SetEnabled(PRBool aEnabled){  PRBool oldState = mDisabled;  mDisabled = ((PR_TRUE == aEnabled) ? PR_FALSE : PR_TRUE);  if ((nsnull != mDocument) && (mDisabled != oldState)) {    mDocument->SetStyleSheetDisabledState(this, mDisabled);  }  return NS_OK;}