Move CSSRuleList to the garbage collected heap

Source/core/css/CSSRuleList.h

 /*
  * (C) 1999-2003 Lars Knoll (knoll@kde.org)
  * (C) 2002-2003 Dirk Mueller (mueller@kde.org)
  * Copyright (C) 2002, 2006, 2012 Apple Computer, Inc.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
  *
@@ skipping 14 matching lines @@
 #include "heap/Handle.h"
 #include "wtf/PassRefPtr.h"
 #include "wtf/RefPtr.h"
 #include "wtf/Vector.h"
 
 namespace WebCore {
 
 class CSSRule;
 class CSSStyleSheet;
 
-class CSSRuleList {
-    WTF_MAKE_NONCOPYABLE(CSSRuleList); WTF_MAKE_FAST_ALLOCATED;
+class CSSRuleList : public NoBaseWillBeGarbageCollectedFinalized<CSSRuleList> {
+    WTF_MAKE_NONCOPYABLE(CSSRuleList);
+    WTF_MAKE_FAST_ALLOCATED_WILL_BE_REMOVED;
 public:
     virtual ~CSSRuleList();
 
+#if !ENABLE(OILPAN)
     virtual void ref() = 0;
     virtual void deref() = 0;
+#endif
 
     virtual unsigned length() const = 0;
     virtual CSSRule* item(unsigned index) const = 0;
 
     virtual CSSStyleSheet* styleSheet() const = 0;
 
+    virtual void trace(Visitor*) { }

[Mads Ager (chromium), 2014/03/10 12:32:57]

Make this a pure virtual as well? (Either that or call it in subclasses
explicitly but there is no point in that.)

[zerny-chromium, 2014/03/10 14:00:21]

The plugin should warn that this trace is not called from the derived classes.
Making it pure-virtual as Mads suggests will resolve the issue.

[Erik Corry, 2014/03/12 10:36:41]

Done.

[Erik Corry, 2014/03/12 10:36:41]

Done.

+
 protected:
     CSSRuleList();
 };
 
 class StaticCSSRuleList FINAL : public CSSRuleList {
 public:
-    static PassRefPtr<StaticCSSRuleList> create() { return adoptRef(new StaticCSSRuleList()); }
+    static PassRefPtrWillBeRawPtr<StaticCSSRuleList> create()
+    {
+        return adoptRefWillBeNoop(new StaticCSSRuleList());
+    }
 
+#if !ENABLE(OILPAN)
     virtual void ref() OVERRIDE { ++m_refCount; }
     virtual void deref() OVERRIDE;
+#endif
 
-    WillBePersistentHeapVector<RefPtrWillBeMember<CSSRule> >& rules() { return m_rules; }
+    WillBeHeapVector<RefPtrWillBeMember<CSSRule> >& rules() { return m_rules; }
 
     virtual CSSStyleSheet* styleSheet() const OVERRIDE { return 0; }
 
+    virtual void trace(Visitor*) OVERRIDE;
+
 private:
     StaticCSSRuleList();
     virtual ~StaticCSSRuleList();
 
     virtual unsigned length() const OVERRIDE { return m_rules.size(); }
     virtual CSSRule* item(unsigned index) const OVERRIDE { return index < m_rules.size() ? m_rules[index].get() : 0; }
 
-    WillBePersistentHeapVector<RefPtrWillBeMember<CSSRule> > m_rules;
+    WillBeHeapVector<RefPtrWillBeMember<CSSRule> > m_rules;
+#if !ENABLE(OILPAN)
     unsigned m_refCount;
+#endif
 };
 
-// The rule owns the live list.
+// The rule owns the live list. FIXME: oilpan: Delete this comment.
 template <class Rule>
 class LiveCSSRuleList FINAL : public CSSRuleList {
 public:
+    static PassOwnPtrWillBeRawPtr<LiveCSSRuleList> create(Rule* rule)
+    {
+        return adoptPtrWillBeNoop(new LiveCSSRuleList(rule));
+    }
+
+#if !ENABLE(OILPAN)
+    virtual void ref() OVERRIDE { m_rule->ref(); }
+    virtual void deref() OVERRIDE { m_rule->deref(); }
+#endif
+
+    virtual void trace(Visitor* visitor) OVERRIDE
+    {
+        CSSRuleList::trace(visitor);

[Mads Ager (chromium), 2014/03/10 12:32:57]

If you make it pure virtual you can leave this one out.

[Erik Corry, 2014/03/12 10:36:41]

Done.

+        visitor->trace(m_rule);
+    }
+
+private:
     LiveCSSRuleList(Rule* rule) : m_rule(rule) { }
 
-    virtual void ref() OVERRIDE { m_rule->ref(); }
-    virtual void deref() OVERRIDE { m_rule->deref(); }
-
-private:
     virtual unsigned length() const OVERRIDE { return m_rule->length(); }
     virtual CSSRule* item(unsigned index) const OVERRIDE { return m_rule->item(index); }
     virtual CSSStyleSheet* styleSheet() const OVERRIDE { return m_rule->parentStyleSheet(); }
 
-    // FIXME: oilpan: This is always a subclass of CSSRule, so it should be
-    // RawPtrWillBeMember<Rule>, but that would leak right now in Oilpan mode:
-    // m_ruleListCSSOMWrapper is an OwnPtr pointing at CSSRuleList, which is a
-    // superclass of this class, and this points at things that have an
-    // m_ruleListCSSOMWrapper field. When LiveCSSRuleList is moved to the GCed
-    // heap, this can be fixed.
-    Rule* m_rule;
+    RawPtrWillBeMember<Rule> m_rule;
 };
 
 } // namespace WebCore
 
 #endif // CSSRuleList_h