Fix issue with setters and their holders in accessors.cc

test/mjsunit/es7/object-observe.js

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 1667 matching lines @@
   { object: fun, name: 'prototype', type: 'update', oldValue: 7 },
 ]);
 
 // Function.prototype should not be observable except on the object itself
 reset();
 var fun = function(){};
 var obj = { __proto__: fun };
 Object.observe(obj, observer.callback);
 obj.prototype = 7;
 Object.deliverChangeRecords(observer.callback);
-observer.assertNotCalled();
-
+observer.assertRecordCount(1);
+observer.assertCallbackRecords([
+  { object: obj, name: 'prototype', type: 'add' },
+]);
 
 // Check that changes in observation status are detected in all IC states and
 // in optimized code, especially in cases usually using fast elements.
 var mutation = [
   "a[i] = v",
   "a[i] ? ++a[i] : a[i] = v",
   "a[i] ? a[i]++ : a[i] = v",
   "a[i] ? a[i] += 1 : a[i] = v",
   "a[i] ? a[i] -= -1 : a[i] = v",
 ];
@@ skipping 88 matching lines @@
     for (var n1 = 0; n1 < 3; ++n1)
       for (var n2 = 0; n2 < 3; ++n2)
         for (var i in mutation)
           TestFastElementsLength(mutation[i], b1 != 0, b2 != 0, 20*n1, 20*n2);
 
 for (var b1 = 0; b1 < 2; ++b1)
   for (var b2 = 0; b2 < 2; ++b2)
     for (var n = 0; n < 3; ++n)
       for (var i in mutationByIncr)
         TestFastElementsLength(mutationByIncr[i], b1 != 0, b2 != 0, 7*n, 7*n+1);