Ignore default reject handler when looking for reject handlers.

src/promise.js

 // Copyright 2012 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.
 
 "use strict";
 
 // This file relies on the fact that the following declaration has been made
 // in runtime.js:
 // var $Object = global.Object
 // var $WeakMap = global.WeakMap
@@ skipping 306 matching lines @@
         );
       }
     } catch (e) {
       deferred.reject(e)
     }
     return deferred.promise;
   }
 
 
   // Utility for debugger
+  
+  function PromiseHasRejectHandlerRecursive(promise) {
+    var queue = GET_PRIVATE(promise, promiseOnReject);
+    if (IS_UNDEFINED(queue)) return false;
+    // Do a depth first search for a reject handler that's not
+    // the default PromiseIdRejectHandler.
+    for (var i = 0; i < queue.length; i += 2) {
+      if (queue[i] != PromiseIdRejectHandler) return true;
+      if (PromiseHasRejectHandlerRecursive(queue[i + 1])) return true;
+    }
+    return false;
+  }
 
   PromiseHasRejectHandler = function PromiseHasRejectHandler() {
     // Mark promise as already having triggered a reject event.
     SET_PRIVATE(this, promiseDebug, true);
-    var queue = GET_PRIVATE(this, promiseOnReject);
-    return !IS_UNDEFINED(queue) && queue.length > 0;
+    return PromiseHasRejectHandlerRecursive(this);
   };
 
   // -------------------------------------------------------------------
   // Install exported functions.
 
   %CheckIsBootstrapping();
   %AddNamedProperty(global, 'Promise', $Promise, DONT_ENUM);
   InstallFunctions($Promise, DONT_ENUM, [
     "defer", PromiseDeferred,
     "accept", PromiseResolved,
     "reject", PromiseRejected,
     "all", PromiseAll,
     "race", PromiseOne,
     "resolve", PromiseCast
   ]);
   InstallFunctions($Promise.prototype, DONT_ENUM, [
     "chain", PromiseChain,
     "then", PromiseThen,
     "catch", PromiseCatch
   ]);
 
 })();