Remove PROHIBITS_OVERWRITING as it is subsumed by non-configurable properties.

include/v8.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.
 
 /** \mainpage V8 API Reference Guide
  *
  * V8 is Google's open source JavaScript engine.
  *
  * This set of documents provides reference material generated from the
  * V8 header file, include/v8.h.
@@ skipping 2054 matching lines @@
     const PropertyCallbackInfo<void>& info);
 
 
 /**
  * Access control specifications.
  *
  * Some accessors should be accessible across contexts.  These
  * accessors have an explicit access control parameter which specifies
  * the kind of cross-context access that should be allowed.
  *
- * Additionally, for security, accessors can prohibit overwriting by
- * accessors defined in JavaScript.  For objects that have such
- * accessors either locally or in their prototype chain it is not
- * possible to overwrite the accessor by using __defineGetter__ or
- * __defineSetter__ from JavaScript code.
+ * TODO(dcarney): Remove PROHIBITS_OVERWRITING as it is now unused.
  */
 enum AccessControl {
   DEFAULT               = 0,
   ALL_CAN_READ          = 1,
   ALL_CAN_WRITE         = 1 << 1,
   PROHIBITS_OVERWRITING = 1 << 2
 };
 
 
 /**
@@ skipping 4540 matching lines @@
  */
 
 
 }  // namespace v8
 
 
 #undef TYPE_CHECK
 
 
 #endif  // V8_H_