Remove support for Object.observe

src/accessors.h

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef V8_ACCESSORS_H_
 #define V8_ACCESSORS_H_
 
 #include "include/v8.h"
 #include "src/allocation.h"
 #include "src/globals.h"
@@ skipping 30 matching lines @@
   V(ScriptName)                   \
   V(ScriptSource)                 \
   V(ScriptType)                   \
   V(ScriptSourceUrl)              \
   V(ScriptSourceMappingUrl)       \
   V(ScriptIsEmbedderDebugScript)  \
   V(StringLength)
 
 #define ACCESSOR_SETTER_LIST(V)        \
   V(ReconfigureToDataProperty)         \
-  V(ObservedReconfigureToDataProperty) \
   V(ArrayLengthSetter)                 \
   V(FunctionPrototypeSetter)
 
 // Accessors contains all predefined proxy accessors.
 
 class Accessors : public AllStatic {
  public:
   // Accessor descriptors.
 #define ACCESSOR_INFO_DECLARATION(name)                   \
   static void name##Getter(                               \
@@ skipping 47 matching lines @@
       Handle<Name> name,
       AccessorNameGetterCallback getter,
       AccessorNameSetterCallback setter,
       PropertyAttributes attributes);
 };
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_ACCESSORS_H_