Changed computation of func.caller to skip some built-in functions.

test/mjsunit/function-caller.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 28 matching lines @@
   f(h);
 }
 h();
 
 // Check called from top-level.
 f(null);
 
 // Check called from eval.
 eval('f(null)');
 
+// Check called from builtin functions. Only show the initially called
+// (publicly exposed) builtin function, not it's internal helper functions.
+[Array.prototype.sort, Array.prototype.sort].sort(f);
+
+"abel".replace(/b/g, function h() {
+   assertEquals(String.prototype.replace, h.caller);
+});