Array.prototype.{reduce, reduceRight}: Wrong order of operations when determining initial value.

test/mjsunit/array-reduce.js

Index: test/mjsunit/array-reduce.js
diff --git a/test/mjsunit/array-reduce.js b/test/mjsunit/array-reduce.js
index 429f34808d74152e25705b296dc584c2f41837e0..94e51440b154edb6dc2a6ae9f2b0cf10ca2f9343 100644
--- a/test/mjsunit/array-reduce.js
+++ b/test/mjsunit/array-reduce.js
@@ -521,3 +521,13 @@ testReduce("reduce", "ArrayManipulationExtender", 10,
             [3, 3, 2, [1, 2, 3, 4, 4, 5], 6],
             [6, 4, 3, [1, 2, 3, 4, 4, 5, 6], 10],
            ], arr, extender, 0);
+
+var arr = [];
+Object.defineProperty(arr, "0", { get: function() { delete this[0] },
+  configurable: true });
+assertEquals(undefined, arr.reduce(function(val) { return val }));
+
+var arr = [];
+Object.defineProperty(arr, "0", { get: function() { delete this[0] },
+  configurable: true});
+assertEquals(undefined, arr.reduceRight(function(val) { return val }));