mRuleCascades = nsnull; return NS_OK;
if (mParent) { CSSStyleSheetImpl* parent = (CSSStyleSheetImpl*)mParent; parent->ClearRuleCascades(); }
CSSRuleProcessor::ClearRuleCascades(void){  RuleCascadeData *data = mRuleCascades;  mRuleCascades = nsnull;  while (data) {    RuleCascadeData *next = data->mNext;    delete data;    data = next;  }  mRuleCascades = nsnull;  return NS_OK;}