Add a WebDocument::watchCssSelectors(selectors)

Source/core/dom/Document.h

Index: Source/core/dom/Document.h
diff --git a/Source/core/dom/Document.h b/Source/core/dom/Document.h
index 724a87a6b183a4eb20ede0df5e0b578eb376252f..dcea6ad54fc233ad068b9574221c3079c87b74b5 100644
--- a/Source/core/dom/Document.h
+++ b/Source/core/dom/Document.h
@@ -141,7 +141,9 @@ class SegmentedString;
 class SelectorQueryCache;
 class SerializedScriptValue;
 class Settings;
+class StyleRareNonInheritedData;
 class StyleResolver;
+class StyleRule;
 class StyleSheet;
 class StyleSheetContents;
 class StyleSheetList;
@@ -450,6 +452,11 @@ public:
 
     void evaluateMediaQueryList();
 
+#if ENABLE(CSS_CALLBACKS)
+    void watchCssSelectors(const Vector<String>& selectors);
+    const Vector<RefPtr<StyleRule> >& watchedCallbackSelectors() const { return m_watchedCallbackSelectors; }
+#endif
+
     // Never returns 0.
     FormController* formController();
     Vector<String> formElementsState() const;
@@ -1031,6 +1038,11 @@ public:
 
     bool inStyleRecalc() { return m_inStyleRecalc; }
 
+#if ENABLE(CSS_CALLBACKS)
+    void addSelectorMatch(const String& selector, StyleRareNonInheritedData*);
+    void removeSelectorMatch(const String& selector);
+#endif
+
     // Return a Locale for the default locale if the argument is null or empty.
     Locale& getCachedLocale(const AtomicString& locale = nullAtom);
 
@@ -1126,6 +1138,12 @@ private:
     void addListenerType(ListenerType listenerType) { m_listenerTypes |= listenerType; }
     void addMutationEventListenerTypeIfEnabled(ListenerType);
 
+#if ENABLE(CSS_CALLBACKS)
+    // Runs FrameLoaderClient::selectorMatchChanged with the updated value of
+    // m_callbackSelectorChange.
+    void callbackSelectorChangeTimerFired(Timer<Document>*);
+#endif
+
     void didAssociateFormControlsTimerFired(Timer<Document>*);
 
     void styleResolverThrowawayTimerFired(Timer<Document>*);
@@ -1344,6 +1362,18 @@ private:
     
     RefPtr<NamedFlowCollection> m_namedFlows;
 
+#if ENABLE(CSS_CALLBACKS)
+    Vector<RefPtr<StyleRule> > m_watchedCallbackSelectors;
+    // Maps a CSS selector string with a -webkit-callback property to the number
+    // of matching RenderStyle objects in this document.
+    HashMap<String, int> m_matchingCallbackSelectors;
+    // Selectors are relative to m_matchingCallbackSelectors's contents at
+    // the previous call to selectorMatchChanged.
+    HashSet<String> m_addedSelectors;
+    HashSet<String> m_removedSelectors;
+    Timer<Document> m_callbackSelectorChangeTimer;
+#endif
+
     RefPtr<DOMSecurityPolicy> m_domSecurityPolicy;
 
     void sharedObjectPoolClearTimerFired(Timer<Document>*);