[proxies] Implement Proxy.revocable.

src/objects.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_OBJECTS_H_
 #define V8_OBJECTS_H_
 
 #include <iosfwd>
 
 #include "src/allocation.h"
@@ skipping 9482 matching lines @@
   DISALLOW_IMPLICIT_CONSTRUCTORS(WeakCell);
 };
 
 
 // The JSProxy describes EcmaScript Harmony proxies
 class JSProxy: public JSReceiver {
  public:
   // [handler]: The handler property.
   DECL_ACCESSORS(handler, Object)
   // [target]: The target property.
-  DECL_ACCESSORS(target, Object)
+  DECL_ACCESSORS(target, JSReceiver)
   // [hash]: The hash code property (undefined if not initialized yet).
   DECL_ACCESSORS(hash, Object)
 
   static MaybeHandle<Context> GetFunctionRealm(Handle<JSProxy> proxy);
 
   DECLARE_CAST(JSProxy)
 
-  bool IsRevoked() const;
+  INLINE(bool IsRevoked() const);
+  static void Revoke(Handle<JSProxy> proxy);
 
   // ES6 9.5.1
   static MaybeHandle<Object> GetPrototype(Handle<JSProxy> receiver);
 
   // ES6 9.5.2
   MUST_USE_RESULT static Maybe<bool> SetPrototype(Handle<JSProxy> proxy,
                                                   Handle<Object> value,
                                                   bool from_javascript,
                                                   ShouldThrow should_throw);
   // ES6 9.5.3
@@ skipping 1195 matching lines @@
     }
     return value;
   }
 };
 
 
 }  // NOLINT, false-positive due to second-order macros.
 }  // NOLINT, false-positive due to second-order macros.
 
 #endif  // V8_OBJECTS_H_