Added Error.captureStackTrace function.

test/mjsunit/stack-traces.js

 // Copyright 2009 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 66 matching lines @@
   function a$b$c$d() { return FAIL; }
   function Wookie() { }
   Wookie.prototype.d = a$b$c$d;
   (new Wookie).d();
 }
 
 function testAnonymousMethod() {
   (function () { FAIL }).call([1, 2, 3]);
 }
 
+function CustomError(message, stripPoint) {
+  this.message = message;
+  Error.captureStackTrace(this, stripPoint);
+}
+
+CustomError.prototype.toString = function () {
+  return "CustomError: " + this.message;
+};
+
+function testDefaultCustomError() {
+  throw new CustomError("hep-hey", undefined);
+}
+
+function testStrippedCustomError() {
+  throw new CustomError("hep-hey", CustomError);
+}
+
 // Utility function for testing that the expected strings occur
 // in the stack trace produced when running the given function.
-function testTrace(fun, expected) {
+function testTrace(fun, expected, unexpected) {
   var threw = false;
   try {
     fun();
   } catch (e) {
     for (var i = 0; i < expected.length; i++) {
       assertTrue(e.stack.indexOf(expected[i]) != -1);
     }
+    if (unexpected) {
+      for (var i = 0; i < unexpected.length; i++) {
+        assertEquals(e.stack.indexOf(unexpected[i]), -1);
+      }
+    }
     threw = true;
   }
   assertTrue(threw);
 }
 
 // Test that the error constructor is not shown in the trace
 function testCallerCensorship() {
   var threw = false;
   try {
     FAIL;
@@ skipping 51 matching lines @@
 testTrace(testArrayNative, ["Array.map (native)"]);
 testTrace(testNested, ["at one", "at two", "at three"]);
 testTrace(testMethodNameInference, ["at Foo.bar"]);
 testTrace(testImplicitConversion, ["at Nirk.valueOf"]);
 testTrace(testEval, ["at Doo (eval at testEval"]);
 testTrace(testNestedEval, ["eval at Inner (eval at Outer"]);
 testTrace(testValue, ["at Number.causeError"]);
 testTrace(testConstructor, ["new Plonk"]);
 testTrace(testRenamedMethod, ["Wookie.a$b$c$d [as d]"]);
 testTrace(testAnonymousMethod, ["Array.<anonymous>"]);
+testTrace(testDefaultCustomError, ["hep-hey", "new CustomError"],
+    ["collectStackTrace"]);
+testTrace(testStrippedCustomError, ["hep-hey"], ["new CustomError",
+    "collectStackTrace"]);
 
 testCallerCensorship();
 testUnintendedCallerCensorship();
 testErrorsDuringFormatting();