Add a WebDocument::watchCssSelectors(selectors)

Source/core/page/UseCounter.cpp

Index: Source/core/page/UseCounter.cpp
diff --git a/Source/core/page/UseCounter.cpp b/Source/core/page/UseCounter.cpp
index 4e16de2575e1f5027e55c0ea024d48eb77f71a60..f818bcbc8287cb29fc34a18b4af71e89ca834ba9 100644
--- a/Source/core/page/UseCounter.cpp
+++ b/Source/core/page/UseCounter.cpp
@@ -494,6 +494,7 @@ int UseCounter::mapCSSPropertyIdToCSSSampleIdForHistogram(int id)
     case CSSPropertyAnimationTimingFunction: return 432;
     case CSSPropertyObjectFit: return 433;
     case CSSPropertyPaintOrder: return 434;
+    case CSSPropertyInternalCallback: return 435;
 
     // Add new features above this line (don't change the assigned numbers of the existing
     // items) and update maximumCSSSampleId() with the new maximum value.
@@ -508,7 +509,7 @@ int UseCounter::mapCSSPropertyIdToCSSSampleIdForHistogram(int id)
     return 0;
 }
 
-static int maximumCSSSampleId() { return 434; }
+static int maximumCSSSampleId() { return 435; }
 
 UseCounter::UseCounter()
 {