Implement handling of arrow functions in the parser

src/v8natives.js

 // Copyright 2012 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 1741 matching lines @@
   if (!IS_STRING(source) || %FunctionIsBuiltin(func)) {
     var name = %FunctionGetName(func);
     if (name) {
       // Mimic what KJS does.
       return 'function ' + name + '() { [native code] }';
     } else {
       return 'function () { [native code] }';
     }
   }
 
+  if (%FunctionIsArrow(func))
+    return source;
+
   var name = %FunctionNameShouldPrintAsAnonymous(func)
       ? 'anonymous'
       : %FunctionGetName(func);
   var head = %FunctionIsGenerator(func) ? 'function* ' : 'function ';
   return head + name + source;
 }
 
 
 function FunctionToString() {
   return FunctionSourceString(this);
@@ skipping 141 matching lines @@
     for (var i = 0; i < microtasks.length; i++) {
       microtasks[i]();
     }
   }
 }
 
 function EnqueueExternalMicrotask(fn) {
   GetMicrotaskQueue().push(fn);
   %SetMicrotaskPending(true);
 }