Add a WebDocument::watchCssSelectors(selectors)

Source/core/css/resolver/StyleResolverState.h

Index: Source/core/css/resolver/StyleResolverState.h
diff --git a/Source/core/css/resolver/StyleResolverState.h b/Source/core/css/resolver/StyleResolverState.h
index 098d7687e43ff2120cae8d90d9d38a056cfe6b8c..f3e91ae159a65176622ce69ee95106508579eb9f 100644
--- a/Source/core/css/resolver/StyleResolverState.h
+++ b/Source/core/css/resolver/StyleResolverState.h
@@ -39,6 +39,7 @@ namespace WebCore {
 class FillLayer;
 class FontDescription;
 class RenderRegion;
+class StyleRule;
 
 class StyleResolverState {
 WTF_MAKE_NONCOPYABLE(StyleResolverState);
@@ -59,7 +60,11 @@ public:
     , m_lineHeightValue(0)
     , m_fontDirty(false)
     , m_hasUAAppearance(false)
-    , m_backgroundData(BackgroundFillLayer) { }
+    , m_backgroundData(BackgroundFillLayer)
+#if ENABLE(CSS_CALLBACKS)
+    , m_rule(0)
+#endif
+    { }
 
 public:
     void initForStyleResolve(Document*, Element*, RenderStyle* parentStyle = 0, RenderRegion* regionForStyling = 0);
@@ -76,6 +81,7 @@ public:
     void setStyle(PassRefPtr<RenderStyle> style) { m_style = style; }
     RenderStyle* style() const { return m_style.get(); }
     PassRefPtr<RenderStyle> takeStyle() { return m_style.release(); }
+    PassRefPtr<RenderStyle> takeStyleAndClear();
 
     const ContainerNode* parentNode() const { return m_parentNode; }
     void setParentStyle(PassRefPtr<RenderStyle> parentStyle) { m_parentStyle = parentStyle; }
@@ -88,6 +94,10 @@ public:
     void setElementAffectedByClassRules(bool isAffected) { m_elementAffectedByClassRules = isAffected; }
     bool elementAffectedByClassRules() const { return m_elementAffectedByClassRules; }
 
+#if ENABLE(CSS_CALLBACKS)
+    void setRule(StyleRule* rule) { m_rule = rule; }
+    const StyleRule* rule() const { return m_rule; }
+#endif
     void setApplyPropertyToRegularStyle(bool isApply) { m_applyPropertyToRegularStyle = isApply; }
     void setApplyPropertyToVisitedLinkStyle(bool isApply) { m_applyPropertyToVisitedLinkStyle = isApply; }
     bool applyPropertyToRegularStyle() const { return m_applyPropertyToRegularStyle; }
@@ -155,8 +165,11 @@ private:
     FillLayer m_backgroundData;
     Color m_backgroundColor;
     ElementStyleResources m_elementStyleResources;
-};
 
+#if ENABLE(CSS_CALLBACKS)
+    StyleRule* m_rule;
+#endif
+};
 } // namespace WebCore
 
 #endif // StyleResolverState_h