Remove Object.observe UseCounter and deprecation warning

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 607 matching lines @@
         V8SVGSVGElement_GetElementById_Method = 778,
         ElementCreateShadowRootMultiple = 779,
         V8MessageChannel_Constructor = 780,
         V8MessagePort_PostMessage_Method = 781,
         V8MessagePort_Start_Method = 782,
         V8MessagePort_Close_Method = 783,
         MessagePortsTransferred = 784,
         CSSKeyframesRuleAnonymousIndexedGetter = 785,
         V8Screen_AvailLeft_AttributeGetter = 786,
         V8Screen_AvailTop_AttributeGetter = 787,
-        ObjectObserve = 788,
         V8SVGFEConvolveMatrixElement_PreserveAlpha_AttributeGetter = 791,
         V8SVGStyleElement_Disabled_AttributeGetter = 798,
         V8SVGStyleElement_Disabled_AttributeSetter = 799,
         InputTypeFileSecureOrigin = 801,
         InputTypeFileInsecureOrigin = 802,
         ElementAttachShadow = 804,
         V8KeyboardEvent_KeyIdentifier_AttributeGetter = 805,
         V8SecurityPolicyViolationEvent_DocumentURI_AttributeGetter = 806,
         V8SecurityPolicyViolationEvent_BlockedURI_AttributeGetter = 807,
         V8SecurityPolicyViolationEvent_StatusCode_AttributeGetter = 808,
@@ skipping 685 matching lines @@
     friend class UseCounterTest;
     static int m_muteCount;
 
     CountBits m_countBits;
     BitVector m_CSSFeatureBits;
 };
 
 } // namespace blink
 
 #endif // UseCounter_h