Remove Object.observe UseCounter and deprecation warning

third_party/WebKit/Source/bindings/core/v8/V8PerIsolateData.cpp

 /*
  * Copyright (C) 2009 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 95 matching lines @@
     switch (feature) {
     case v8::Isolate::kUseAsm:
         blinkFeature = UseCounter::UseAsm;
         break;
     case v8::Isolate::kBreakIterator:
         blinkFeature = UseCounter::BreakIterator;
         break;
     case v8::Isolate::kLegacyConst:
         blinkFeature = UseCounter::LegacyConst;
         break;
-    case v8::Isolate::kObjectObserve:
-        blinkFeature = UseCounter::ObjectObserve;
-        deprecated = true;
-        break;
     case v8::Isolate::kSloppyMode:
         blinkFeature = UseCounter::V8SloppyMode;
         break;
     case v8::Isolate::kStrictMode:
         blinkFeature = UseCounter::V8StrictMode;
         break;
     case v8::Isolate::kStrongMode:
         blinkFeature = UseCounter::V8StrongMode;
         break;
     case v8::Isolate::kRegExpPrototypeStickyGetter:
@@ skipping 249 matching lines @@
 
 void V8PerIsolateData::addActiveScriptWrappable(ActiveScriptWrappable* wrappable)
 {
     if (!m_activeScriptWrappables)
         m_activeScriptWrappables = new ActiveScriptWrappableSet();
 
     m_activeScriptWrappables->add(wrappable);
 }
 
 } // namespace blink