Do not export natives to runtime via js builtins object.

src/messages.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.
 
 // -------------------------------------------------------------------
 
 var $errorToString;
 var $getStackTraceLine;
 var $internalErrorSymbol;
 var $messageGetPositionInLine;
@@ skipping 997 matching lines @@
     throw MakeTypeError(kCalledOnNonObject, "Error.prototype.toString");
   }
 
   return %ErrorToStringRT(this);
 }
 
 utils.InstallFunctions(GlobalError.prototype, DONT_ENUM,
                        ['toString', ErrorToString]);
 
 $errorToString = ErrorToString;
-$getStackTraceLine = GetStackTraceLine;
 $messageGetPositionInLine = GetPositionInLine;
 $messageGetLineNumber = GetLineNumber;
 $messageGetSourceLine = GetSourceLine;
 $noSideEffectToString = NoSideEffectToString;
 $toDetailString = ToDetailString;
 
 $Error = GlobalError;
 $EvalError = GlobalEvalError;
 $RangeError = GlobalRangeError;
 $ReferenceError = GlobalReferenceError;
@@ skipping 40 matching lines @@
 captureStackTrace = function captureStackTrace(obj, cons_opt) {
   // Define accessors first, as this may fail and throw.
   ObjectDefineProperty(obj, 'stack', { get: StackTraceGetter,
                                        set: StackTraceSetter,
                                        configurable: true });
   %CollectStackTrace(obj, cons_opt ? cons_opt : captureStackTrace);
 };
 
 GlobalError.captureStackTrace = captureStackTrace;
 
+utils.ExportToRuntime(function(to) {
+  to.GetStackTraceLine = GetStackTraceLine;
 });
+
+});