Add a WebDocument::watchCssSelectors(selectors)

public/web/WebDocument.h

Index: public/web/WebDocument.h
diff --git a/public/web/WebDocument.h b/public/web/WebDocument.h
index 8d1d009bdd175b5079fa851455a740f8a042b09d..2d3b6bced2fde53d374dbec0e67cba2d528c2776 100644
--- a/public/web/WebDocument.h
+++ b/public/web/WebDocument.h
@@ -123,6 +123,11 @@ public:
     // WebView.
     WEBKIT_EXPORT void insertUserStyleSheet(const WebString& sourceCode, UserStyleLevel);
 
+    // Arranges to call WebFrameClient::didMatchCss(frame(), ...) when one of
+    // the selectors matches or stops matching an element in this document.
+    // Each call to this method overrides any previous calls.
+    WEBKIT_EXPORT void watchCssSelectors(const WebVector<WebString>& selectors);
+
     WEBKIT_EXPORT WebVector<WebDraggableRegion> draggableRegions() const;
 
 #if WEBKIT_IMPLEMENTATION