Stress GC less by allocating exponentially growing string chunks in JSON.stringify.

test/mjsunit/json.js

 // Copyright 2009 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 250 matching lines @@
               JSON.stringify({ a : 1,
                                b : function() { 1 },
                                c : true,
                                d : function() { 2 } }));
 assertEquals('[1,null,true,null]',
              JSON.stringify([1, function() { 1 }, true, function() { 2 }]));
 assertEquals('"toJSON 123"',
              JSON.stringify({ toJSON : function() { return 'toJSON 123'; } }));
 assertEquals('{"a":321}',
              JSON.stringify({ a : { toJSON : function() { return 321; } } }));
+var counter = 0;
 assertEquals('{"getter":123}',
-             JSON.stringify({ get getter() { return 123; } }));
+             JSON.stringify({ get getter() { counter++; return 123; } }));
+assertEquals(1, counter);
 assertEquals('{"a":"abc","b":"\u1234bc"}',
              JSON.stringify({ a : "abc", b : "\u1234bc" }));
 
+
 var a = { a : 1, b : 2 };
 delete a.a;
 assertEquals('{"b":2}', JSON.stringify(a));
 
 var b = {};
 b.__proto__ = { toJSON : function() { return 321;} };
 assertEquals("321", JSON.stringify(b));
 
 var array = [""];
 var expected = '""';
@@ skipping 171 matching lines @@
 // Parse a non-object value as __proto__. This must not create a
 // __proto__ property different from the original, and should not
 // change the original.
 var o = JSON.parse('{"__proto__":5}');
 assertEquals(Object.prototype, o.__proto__);  // __proto__ isn't changed.
 assertEquals(0, Object.keys(o).length);  // __proto__ isn't added as enumerable.
 
 
 var json = '{"stuff before slash\\\\stuff after slash":"whatever"}';
 assertEquals(json, JSON.stringify(JSON.parse(json)));