[promises] Add %WaitForPromise runtime call to allow tests to reliably wait for promises to be fini…

test/mjsunit/mjsunit.js

 // Copyright 2008 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 131 matching lines @@
 
 // Returns true if given function is optimized.
 var isOptimized;
 
 // Returns true if given function is compiled by Crankshaft.
 var isCrankshafted;
 
 // Returns true if given function is compiled by TurboFan.
 var isTurboFanned;
 
+// Monkey-patchable all-purpose failure handler.
+var failWithMessage;
+
 
 (function () {  // Scope for utility functions.
 
   var ObjectPrototypeToString = Object.prototype.toString;
   var NumberPrototypeValueOf = Number.prototype.valueOf;
   var BooleanPrototypeValueOf = Boolean.prototype.valueOf;
   var StringPrototypeValueOf = String.prototype.valueOf;
   var DatePrototypeValueOf = Date.prototype.valueOf;
   var RegExpPrototypeToString = RegExp.prototype.toString;
   var ArrayPrototypeMap = Array.prototype.map;
@@ skipping 64 matching lines @@
     }
   }
 
 
   function PrettyPrintArrayElement(value, index, array) {
     if (value === undefined && !(index in array)) return "";
     return PrettyPrint(value);
   }
 
 
-  function failWithMessage(message) {
+  failWithMessage = function failWithMessage(message) {
+    print("oh, we failed: " + message);
     throw new MjsUnitAssertionError(message);
   }
 
 
   function fail(expectedText, found, name_opt) {
     var message = "Fail" + "ure";
     if (name_opt) {
       // Fix this when we ditch the old test runner.
       message += " (" + name_opt + ")";
     }
 
     var foundText = PrettyPrint(found);
     if (expectedText.length <= 40 && foundText.length <= 40) {
       message += ": expected <" + expectedText + "> found <" + foundText + ">";
     } else {
       message += ":\nexpected:\n" + expectedText + "\nfound:\n" + foundText;
     }
-    throw new MjsUnitAssertionError(message);
+    return failWithMessage(message);
   }
 
 
   function deepObjectEquals(a, b) {
     var aProps = Object.keys(a);
     aProps.sort();
     var bProps = Object.keys(b);
     bProps.sort();
     if (!deepEquals(aProps, bProps)) {
       return false;
@@ skipping 293 matching lines @@
 
   isTurboFanned = function isTurboFanned(fun) {
     var opt_status = OptimizationStatus(fun, "");
     assertTrue((opt_status & V8OptimizationStatus.kIsFunction) !== 0,
                "not a function");
     return (opt_status & V8OptimizationStatus.kOptimized) !== 0 &&
            (opt_status & V8OptimizationStatus.kTurboFanned) !== 0;
   }
 
 })();