Properly complete in-object slack tracking.

test/mjsunit/regress/regress-crbug-599003.js

Index: test/mjsunit/regress/regress-crbug-599003.js
diff --git a/test/mjsunit/regress/regress-crbug-599003.js b/test/mjsunit/regress/regress-crbug-599003.js
new file mode 100644
index 0000000000000000000000000000000000000000..da29455661b0fac4994bc40ae0f615c488fdea92
--- /dev/null
+++ b/test/mjsunit/regress/regress-crbug-599003.js
@@ -0,0 +1,39 @@
+// Copyright 2016 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.
+
+// Flags: --allow-natives-syntax --expose-gc --verify-heap
+
+function A() {}
+
+function g1() {
+  var obj = new A();
+  obj.v0 = 0;
+  obj.v1 = 0;
+  obj.v2 = 0;
+  obj.v3 = 0;
+  obj.v4 = 0;
+  obj.v5 = 0;
+  obj.v6 = 0;
+  obj.v7 = 0;
+  obj.v8 = 0;
+  obj.v9 = 0;
+  return obj;
+}
+
+function g2() {
+  return new A();
+}
+
+var o = g1();
+%OptimizeFunctionOnNextCall(g2);
+g2();
+o = null;
+gc();
+
+for (var i = 0; i < 20; i++) {
+  var o = new A();
+}
+g2();
+
+gc();  // Boom!