| Index: src/js/prologue.js | 
| diff --git a/src/js/prologue.js b/src/js/prologue.js | 
| index e564eb5cf803f7d1662a4bab272f62471ff8f20b..e51ab558b6605e62d87b6be93ed9f34122f30e8b 100644 | 
| --- a/src/js/prologue.js | 
| +++ b/src/js/prologue.js | 
| @@ -266,7 +266,7 @@ utils.PostDebug = PostDebug; | 
|  | 
| // ----------------------------------------------------------------------- | 
|  | 
| -%OptimizeObjectForAddingMultipleProperties(extrasUtils, 5); | 
| +%OptimizeObjectForAddingMultipleProperties(extrasUtils, 7); | 
|  | 
| extrasUtils.logStackTrace = function logStackTrace() { | 
| %DebugTrace(); | 
| @@ -307,6 +307,15 @@ extrasUtils.uncurryThis = function uncurryThis(func) { | 
| }; | 
| }; | 
|  | 
| +// We pass true to trigger the debugger's on exception handler. | 
| +extrasUtils.rejectPromise = function rejectPromise(promise, reason) { | 
| +  %promise_internal_reject(promise, reason, true); | 
| +} | 
| + | 
| +extrasUtils.markPromiseAsHandled = function markPromiseAsHandled(promise) { | 
| +  %PromiseMarkAsHandled(promise); | 
| +}; | 
| + | 
| %ToFastProperties(extrasUtils); | 
|  | 
| }) | 
|  |