Error.captureStackTrace should define "stack" property as configurable.

src/messages.js

Index: src/messages.js
diff --git a/src/messages.js b/src/messages.js
index 28af372b7f2fbc2f1897222e4b9b32eebda4ca57..ee5b1950a7f2bd6155eca93b2a60240cf5c785f4 100644
--- a/src/messages.js
+++ b/src/messages.js
@@ -1144,7 +1144,8 @@ var StackTraceSetter = function(v) {
 var captureStackTrace = function captureStackTrace(obj, cons_opt) {
   // Define accessors first, as this may fail and throw.
   ObjectDefineProperty(obj, 'stack', { get: StackTraceGetter,
-                                       set: StackTraceSetter});
+                                       set: StackTraceSetter,
+                                       configurable: true });
   %CollectStackTrace(obj, cons_opt ? cons_opt : captureStackTrace);
 }