[proxies] Improve error messages.

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 1829 matching lines @@
 
   // ES6 9.1.6.1
   MUST_USE_RESULT static Maybe<bool> OrdinaryDefineOwnProperty(
       Isolate* isolate, Handle<JSObject> object, Handle<Object> key,
       PropertyDescriptor* desc, ShouldThrow should_throw);
   MUST_USE_RESULT static Maybe<bool> OrdinaryDefineOwnProperty(
       LookupIterator* it, PropertyDescriptor* desc, ShouldThrow should_throw);
   // ES6 9.1.6.2
   MUST_USE_RESULT static Maybe<bool> IsCompatiblePropertyDescriptor(
       Isolate* isolate, bool extensible, PropertyDescriptor* desc,
-      PropertyDescriptor* current, Handle<Name> property_name);
+      PropertyDescriptor* current, Handle<Name> property_name,
+      ShouldThrow should_throw);
   // ES6 9.1.6.3
   // |it| can be NULL in cases where the ES spec passes |undefined| as the
   // receiver. Exactly one of |it| and |property_name| must be provided.
   MUST_USE_RESULT static Maybe<bool> ValidateAndApplyPropertyDescriptor(
       Isolate* isolate, LookupIterator* it, bool extensible,
       PropertyDescriptor* desc, PropertyDescriptor* current,
       ShouldThrow should_throw, Handle<Name> property_name = Handle<Name>());
 
   MUST_USE_RESULT static Maybe<bool> GetOwnPropertyDescriptor(
       Isolate* isolate, Handle<JSReceiver> object, Handle<Object> key,
@@ skipping 8842 matching lines @@
     }
     return value;
   }
 };
 
 
 }  // NOLINT, false-positive due to second-order macros.
 }  // NOLINT, false-positive due to second-order macros.
 
 #endif  // V8_OBJECTS_H_