[proxies] Fix bogus cast in HasOwnPropertyImplementation

src/runtime/runtime-object.cc

 // Copyright 2014 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.
 
 #include "src/runtime/runtime-utils.h"
 
 #include "src/arguments.h"
 #include "src/bootstrapper.h"
 #include "src/debug/debug.h"
 #include "src/isolate-inl.h"
@@ skipping 653 matching lines @@
                                             Handle<JSObject> object,
                                             Handle<Name> key) {
   Maybe<bool> maybe = JSReceiver::HasOwnProperty(object, key);
   if (!maybe.IsJust()) return isolate->heap()->exception();
   if (maybe.FromJust()) return isolate->heap()->true_value();
   // Handle hidden prototypes.  If there's a hidden prototype above this thing
   // then we have to check it for properties, because they are supposed to
   // look like they are on this object.
   PrototypeIterator iter(isolate, object);
   if (!iter.IsAtEnd() &&
-      Handle<JSObject>::cast(PrototypeIterator::GetCurrent(iter))
+      PrototypeIterator::GetCurrent<HeapObject>(iter)
           ->map()
           ->is_hidden_prototype()) {
     // TODO(verwaest): The recursion is not necessary for keys that are array
     // indices. Removing this.
     // Casting to JSObject is fine because JSProxies are never used as
     // hidden prototypes.
     return HasOwnPropertyImplementation(
-        isolate, Handle<JSObject>::cast(PrototypeIterator::GetCurrent(iter)),
-        key);
+        isolate, PrototypeIterator::GetCurrent<JSObject>(iter), key);
   }
   RETURN_FAILURE_IF_SCHEDULED_EXCEPTION(isolate);
   return isolate->heap()->false_value();
 }
 
 
 RUNTIME_FUNCTION(Runtime_HasOwnProperty) {
   HandleScope scope(isolate);
   DCHECK(args.length() == 2);
   CONVERT_ARG_HANDLE_CHECKED(Object, object, 0)
@@ skipping 719 matching lines @@
 
 RUNTIME_FUNCTION(Runtime_ObjectDefineProperties) {
   HandleScope scope(isolate);
   DCHECK(args.length() == 2);
   CONVERT_ARG_HANDLE_CHECKED(Object, o, 0);
   CONVERT_ARG_HANDLE_CHECKED(Object, properties, 1);
   return JSReceiver::DefineProperties(isolate, o, properties);
 }
 }  // namespace internal
 }  // namespace v8