bindings: Skip undefined property descriptors when creating records.

third_party/WebKit/LayoutTests/bindings/record-type.html

Index: third_party/WebKit/LayoutTests/bindings/record-type.html
diff --git a/third_party/WebKit/LayoutTests/bindings/record-type.html b/third_party/WebKit/LayoutTests/bindings/record-type.html
index 190c21bd850f3ffd2ae6c0262f2eaf98ea683dee..8100f562caabd8c91545cf4a016005de739e3b1a 100644
--- a/third_party/WebKit/LayoutTests/bindings/record-type.html
+++ b/third_party/WebKit/LayoutTests/bindings/record-type.html
@@ -31,6 +31,24 @@
  test(() => {
    let recordTest = internals.recordTest();
 
+   let record = {'foo': 42, 'quux': 34};
+   let handler = {
+     getOwnPropertyDescriptor: (target, name) => {
+       if (name == 'quux')
+         return undefined;
+       return Reflect.getOwnPropertyDescriptor(target, name);
+     }
+   };
+   var recordProxy = new Proxy(record, handler);
+   recordTest.setStringLongRecord(record);
+   assert_record_equals(
+     recordTest.getStringLongRecord(), [['foo', 42]],
+     "Entries whose getOwnPropertyDescriptor return undefined are skipped");
+ }, "Test GetOwnPropertyDescriptor() returning undefined");
+
+ test(() => {
+   let recordTest = internals.recordTest();
+
    recordTest.setStringLongRecord({a: true, false: null, c: "foo"});
    assert_record_equals(recordTest.getStringLongRecord(),
                         [['a', 1], ['false', 0], ['c', 0]],