[proxies] Make Object.prototype.isPrototypeOf work with proxies.

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 1287 matching lines @@
       LanguageMode language_mode = SLOPPY);
 
   MUST_USE_RESULT static inline MaybeHandle<Object> SetElement(
       Isolate* isolate, Handle<Object> object, uint32_t index,
       Handle<Object> value, LanguageMode language_mode);
 
   // Get the first non-hidden prototype.
   static inline MaybeHandle<Object> GetPrototype(Isolate* isolate,
                                                  Handle<Object> receiver);
 
-  bool HasInPrototypeChain(Isolate* isolate, Object* object);
+  MUST_USE_RESULT static Maybe<bool> HasInPrototypeChain(Isolate* isolate,
+                                                         Handle<Object> object,
+                                                         Handle<Object> proto);
 
   // Returns the permanent hash code associated with this object. May return
   // undefined if not yet created.
   Object* GetHash();
 
   // Returns undefined for JSObjects, but returns the hash code for simple
   // objects.  This avoids a double lookup in the cases where we know we will
   // add the hash to the JSObject if it does not already exist.
   Object* GetSimpleHash();
 
@@ skipping 9397 matching lines @@
     }
     return value;
   }
 };
 
 
 }  // NOLINT, false-positive due to second-order macros.
 }  // NOLINT, false-positive due to second-order macros.
 
 #endif  // V8_OBJECTS_H_