void CSSStyleSheet::willMutateRules()
{
// If we are the only client it is safe to mutate.
if (m_contents->hasOneClient() && !m_contents->isInMemoryCache()) {
m_contents->setMutable();
return;
}
// Only cacheable stylesheets should have multiple clients.
ASSERT(m_contents->isCacheable());
// Copy-on-write.
m_contents->unregisterClient(this);
m_contents = m_contents->copy();
m_contents->registerClient(this);
m_contents->setMutable();
// Any existing CSSOM wrappers need to be connected to the copied child rules.
reattachChildRuleCSSOMWrappers();
}
void CSSStyleSheet::willMutateRules() {
// If we are the only client it is safe to mutate.
if (!m_contents->isUsedFromTextCache() &&
!m_contents->isReferencedFromResource()) {
m_contents->clearRuleSet();
m_contents->setMutable();
return;
}
// Only cacheable stylesheets should have multiple clients.
DCHECK(m_contents->isCacheableForStyleElement() ||
m_contents->isCacheableForResource());
// Copy-on-write.
m_contents->unregisterClient(this);
m_contents = m_contents->copy();
m_contents->registerClient(this);
m_contents->setMutable();
// Any existing CSSOM wrappers need to be connected to the copied child rules.
reattachChildRuleCSSOMWrappers();
}
void CSSStyleSheet::willMutateRules()
{
// If we are the only client it is safe to mutate.
if (m_contents->clientSize() <= 1 && !m_contents->isReferencedFromResource()) {
m_contents->clearRuleSet();
if (Document* document = ownerDocument())
m_contents->removeSheetFromCache(document);
m_contents->setMutable();
return;
}
// Only cacheable stylesheets should have multiple clients.
ASSERT((isStyleElement(ownerNode()) && m_contents->isCacheableForStyleElement())
|| m_contents->isCacheableForResource());
// Copy-on-write.
m_contents->unregisterClient(this);
m_contents = m_contents->copy();
m_contents->registerClient(this);
m_contents->setMutable();
// Any existing CSSOM wrappers need to be connected to the copied child rules.
reattachChildRuleCSSOMWrappers();
}
