Add initial UMA metrics for ScrollAnchoring

third_party/WebKit/Source/core/frame/UseCounter.h

 /*
  * Copyright (C) 2012 Google, Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 1073 matching lines @@
         HTMLMediaElementLoadNetworkEmptyNotPaused = 1265,
         EventRelatedTargetScoped = 1266,
         V8Window_WebkitSpeechGrammar_ConstructorGetter = 1267,
         V8Window_WebkitSpeechGrammarList_ConstructorGetter = 1268,
         V8Window_WebkitSpeechRecognition_ConstructorGetter = 1269,
         V8Window_WebkitSpeechRecognitionError_ConstructorGetter = 1270,
         V8Window_WebkitSpeechRecognitionEvent_ConstructorGetter = 1271,
         V8Window_SpeechSynthesis_AttributeGetter = 1272,
         V8IDBFactory_WebkitGetDatabaseNames_Method = 1273,
         ImageDocument = 1274,
+        ScrollAnchored = 1275,
 
         // 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/
         // to update the UMA mapping.
         NumberOfFeatures, // This enum value must be last.
     };
 
     // "count" sets the bit for this feature to 1. Repeated calls are ignored.
     static void count(const Frame*, Feature);
@@ skipping 74 matching lines @@
     friend class UseCounterTest;
     static int m_muteCount;
 
     CountBits m_countBits;
     BitVector m_CSSFeatureBits;
 };
 
 } // namespace blink
 
 #endif // UseCounter_h