Add a WebDocument::watchCssSelectors(selectors)

Source/core/rendering/style/RenderStyle.h

Index: Source/core/rendering/style/RenderStyle.h
diff --git a/Source/core/rendering/style/RenderStyle.h b/Source/core/rendering/style/RenderStyle.h
index 6d60e8da2f63b5b9a4deb3e129ed133e1f741bbd..c7c1854690d6cb744db595a4c242d888e8514eab 100644
--- a/Source/core/rendering/style/RenderStyle.h
+++ b/Source/core/rendering/style/RenderStyle.h
@@ -732,6 +732,9 @@ public:
     EBoxPack boxPack() const { return static_cast<EBoxPack>(rareNonInheritedData->m_deprecatedFlexibleBox->pack); }
 
     int order() const { return rareNonInheritedData->m_order; }
+#if ENABLE(CSS_CALLBACKS)
+    const Vector<String>& callbackSelectors() const { return rareNonInheritedData->m_callbackSelectors; }
+#endif
     float flexGrow() const { return rareNonInheritedData->m_flexibleBox->m_flexGrow; }
     float flexShrink() const { return rareNonInheritedData->m_flexibleBox->m_flexShrink; }
     Length flexBasis() const { return rareNonInheritedData->m_flexibleBox->m_flexBasis; }
@@ -1186,6 +1189,10 @@ public:
     void setFlexShrink(float f) { SET_VAR(rareNonInheritedData.access()->m_flexibleBox, m_flexShrink, f); }
     void setFlexBasis(Length length) { SET_VAR(rareNonInheritedData.access()->m_flexibleBox, m_flexBasis, length); }
     void setOrder(int o) { SET_VAR(rareNonInheritedData, m_order, o); }
+#if ENABLE(CSS_CALLBACKS)
+    void addCallbackSelector(const String& selector, Document*);
+    void removeCallbackSelector(const String& selector);
+#endif
     void setAlignContent(EAlignContent p) { SET_VAR(rareNonInheritedData, m_alignContent, p); }
     void setAlignItems(EAlignItems a) { SET_VAR(rareNonInheritedData, m_alignItems, a); }
     void setAlignSelf(EAlignItems a) { SET_VAR(rareNonInheritedData, m_alignSelf, a); }