Add UseCounter for web components related CSS selectors

Source/core/frame/UseCounter.h

Index: Source/core/frame/UseCounter.h
diff --git a/Source/core/frame/UseCounter.h b/Source/core/frame/UseCounter.h
index e76d3cfdfe6e09982a6d3ac7e7ced033d13e75b3..8d0abe4a6564e2beb0a70bb82bb8cdeffddac986 100644
--- a/Source/core/frame/UseCounter.h
+++ b/Source/core/frame/UseCounter.h
@@ -463,6 +463,12 @@ public:
         HTMLImportsAsyncAttribute = 463,
         FontFaceSetReady = 464,
         XMLHttpRequestSynchronous = 465,
+        CSSSelectorPseudoUnresolved = 466,
+        CSSSelectorPseudoShadow = 467,
+        CSSSelectorPseudoContent = 468,
+        CSSSelectorPseudoHost = 469,
+        CSSSelectorPseudoHostContext = 470,
+        CSSDeepCombinator = 471,
         // Add new features immediately above this line. Don't change assigned
         // numbers of any item, and don't reuse removed slots.
         // Also, run update_use_counter_feature_enum.py in chromium/src/tools/metrics/histograms/