Explore the possibility of implementing the CSS Region interface.

Source/core/css/CSSRegion.h

Index: Source/core/css/CSSRegion.h
diff --git a/Source/core/css/CSSFilterRule.h b/Source/core/css/CSSRegion.h
similarity index 62%
copy from Source/core/css/CSSFilterRule.h
copy to Source/core/css/CSSRegion.h
index 9e605873553aef3821cd10a78e96aa14b9ab9a55..0bdbf68bb854329e81eac6a5f03837fe1fdb0d4f 100644
--- a/Source/core/css/CSSFilterRule.h
+++ b/Source/core/css/CSSRegion.h
@@ -27,37 +27,52 @@
  * SUCH DAMAGE.
  */
 
-#ifndef CSSFilterRule_h
-#define CSSFilterRule_h
+#ifndef CSSRegion_h
+#define CSSRegion_h
 
-#include "core/css/CSSRule.h"
+#include "core/dom/Element.h"
+#include "core/dom/Range.h"
+
+#include "wtf/RefCounted.h"
+#include "wtf/RefPtr.h"
 
 namespace WebCore {
 
-class CSSStyleDeclaration;
-class StyleRuleFilter;
-class StyleRuleCSSStyleDeclaration;
+class Range;
+class RenderRegion;
 
-class CSSFilterRule : public CSSRule {
+class CSSRegion : public RefCounted<CSSRegion> {
 public:
-    static PassRefPtr<CSSFilterRule> create(StyleRuleFilter* rule, CSSStyleSheet* sheet) { return adoptRef(new CSSFilterRule(rule, sheet)); }
+    static PassRefPtr<CSSRegion> create(const RenderRegion* region)

[Inactive, 2013/10/25 17:48:50]

Would be nice to use a reference instead of a pointer as it cannot be null

+    {
+        return adoptRef(new CSSRegion(region));
+    }
 
-    virtual ~CSSFilterRule();
+    static const AtomicString& webkitRegionOverset(const Element* element)

[Inactive, 2013/10/25 17:48:50]

Would be nice to use a reference instead of a pointer as it cannot be null

+    {
+        return element->webkitRegionOverset();
+    }
 
-    virtual CSSRule::Type type() const OVERRIDE { return WEBKIT_FILTER_RULE; }
-    virtual String cssText() const OVERRIDE;
-    virtual void reattach(StyleRuleBase*) OVERRIDE;
+    static Vector<RefPtr<Range>> webkitGetRegionFlowRanges(const Element* element)

[Inactive, 2013/10/25 17:48:50]

'>>' do we support C++11 on all platforms now?

[Inactive, 2013/10/25 17:48:50]

Would be nice to use a reference instead of a pointer as it cannot be null

+    {
+        return element->webkitGetRegionFlowRanges();
+    }
 
-    CSSStyleDeclaration* style() const;
+    const RenderRegion* region()

[Inactive, 2013/10/25 17:48:50]

This getter could be const and return a reference.

+    {
+        return m_region;
+    }
 
 private:
-    CSSFilterRule(StyleRuleFilter*, CSSStyleSheet* parent);
+    CSSRegion(const RenderRegion* region)
+    : m_region(region)
+    {
 
-    RefPtr<StyleRuleFilter> m_filterRule;
-    mutable RefPtr<StyleRuleCSSStyleDeclaration> m_propertiesCSSOMWrapper;
-};
+    }
 
-}
+    const RenderRegion* m_region;

[abarth-chromium, 2013/10/25 16:56:20]

How are the lifetimes of CSSRegion and RenderRegion related?  CSSRegion is
RefCounted, which makes me worry that it could out-live RenderRegion.

+};
 
+} // namespace WebCore
 
-#endif // CSSFilterRule_h
+#endif // CSSRegion_h