Measure the usage of <ol>.start with |reversed| and no |start| attribute.

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 1589 matching lines @@
     kCredentialManagerCustomFetch = 1988,
     kNetInfoRtt = 1989,
     kNetInfoDownlink = 1990,
     kShapeDetection_BarcodeDetectorConstructor = 1991,
     kShapeDetection_FaceDetectorConstructor = 1992,
     kShapeDetection_TextDetectorConstructor = 1993,
     kCredentialManagerCredentialRequestOptionsOnlyUnmediated = 1994,
     kInertAttribute = 1995,
     kPluginInstanceAccessFromIsolatedWorld = 1996,
     kPluginInstanceAccessFromMainWorld = 1997,
+    kHTMLOListElementReversedWithoutStart = 1998,

[tkent, 2017/05/24 23:41:55]

kHTMLOListElementStartGetterReversedWithoutStartAttribute is more correct.

[Shanmuga Pandi, 2017/05/25 06:04:31]

Done.

 
     // 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.
     kNumberOfFeatures,  // This enum value must be last.
   };
 
   // An interface to observe UseCounter changes. Note that this is never
   // notified when the counter is disabled by |m_muteCount| or when |m_context|
@@ skipping 97 matching lines @@
     // Tracks what features/properties need to be reported to the legacy
     // histograms.
     BitVector feature_bits_;
     BitVector css_bits_;
   } legacy_counter_;
 };
 
 }  // namespace blink
 
 #endif  // UseCounter_h