Move MediaQuery classes off BlinkGC heap

third_party/WebKit/Source/core/css/CSSStyleSheet.cpp

Index: third_party/WebKit/Source/core/css/CSSStyleSheet.cpp
diff --git a/third_party/WebKit/Source/core/css/CSSStyleSheet.cpp b/third_party/WebKit/Source/core/css/CSSStyleSheet.cpp
index 22d89cc955a62693ca24005d59aeb651d33146fa..b77323c4eddb1f8c51441ed2bb7b044a8d00603c 100644
--- a/third_party/WebKit/Source/core/css/CSSStyleSheet.cpp
+++ b/third_party/WebKit/Source/core/css/CSSStyleSheet.cpp
@@ -202,8 +202,8 @@ void CSSStyleSheet::setDisabled(bool disabled) {
   didMutate();
 }
 
-void CSSStyleSheet::setMediaQueries(MediaQuerySet* mediaQueries) {
-  m_mediaQueries = mediaQueries;
+void CSSStyleSheet::setMediaQueries(RefPtr<MediaQuerySet> mediaQueries) {
+  m_mediaQueries = std::move(mediaQueries);
   if (m_mediaCSSOMWrapper && m_mediaQueries)
     m_mediaCSSOMWrapper->reattach(m_mediaQueries.get());
 }
@@ -214,7 +214,7 @@ bool CSSStyleSheet::matchesMediaQueries(const MediaQueryEvaluator& evaluator) {
 
   if (!m_mediaQueries)
     return true;
-  return evaluator.eval(m_mediaQueries, &m_viewportDependentMediaQueryResults,
+  return evaluator.eval(*m_mediaQueries, &m_viewportDependentMediaQueryResults,
                         &m_deviceDependentMediaQueryResults);
 }
 
@@ -444,9 +444,6 @@ void CSSStyleSheet::setText(const String& text) {
 
 DEFINE_TRACE(CSSStyleSheet) {
   visitor->trace(m_contents);
-  visitor->trace(m_mediaQueries);
-  visitor->trace(m_viewportDependentMediaQueryResults);
-  visitor->trace(m_deviceDependentMediaQueryResults);
   visitor->trace(m_ownerNode);
   visitor->trace(m_ownerRule);
   visitor->trace(m_mediaCSSOMWrapper);