Make arguments and caller always be null on native functions (fixes issue 1548 and issue 1643).

Make arguments and caller always be null on native functions (fixes issue 1548 and issue 1643).

With this change we follow Firefox, Safari has a slightly different approach where the property is just not there (at least according to GetOwnProperty). 
Committed: http://code.google.com/p/v8/source/detail?r=9093

[Rico, 2011-09-01 08:15:51]

Kevin: removing the arguments property should not be a problem right?

[Lasse Reichstein, 2011-09-01 08:23:49]

LGTM.
We create the arguments object dynamically in the accessor, so not calling the
accessor should be perfectly safe. There won't be anybody trying to update the
property and failing.

I don't think there'll be any non-malicious code relying on reading .arguments
of built-in functions.

http://codereview.chromium.org/7792054/diff/1/src/v8natives.js
File src/v8natives.js (right):

http://codereview.chromium.org/7792054/diff/1/src/v8natives.js#newcode58
src/v8natives.js:58: %IgnoreAttributesAndSetProperty(f, "caller",
Add comment that we don't match Safari, but we do match Firefox (and possibly
IE).

http://codereview.chromium.org/7792054/diff/1/src/v8natives.js#newcode64
src/v8natives.js:64: 
Add a test that this works? E.g., 
[1].map(function() { assertEquals(null, [].map.caller); assertEquals(null,
[].map.arguments); }

[Rico, 2011-09-01 08:35:11]

Comment addressed and left out regression test file added

[Kevin Millikin (Chromium), 2011-09-01 09:19:08]

LGTM.  The test should probably be repeated for .arguments for completeness.