Remove arguments shadow from scopes, stop rewriting parameters.

[Arguments] Remove arguments shadow from scopes, stop rewriting parameters.

Do not rewrite parameters in functions using the arguments object, access
them directly.  They are allocated to the context in preparation for
capturing by the arguments object.

The arguments shadow object is removed from scopes, because there is no
longer any reason to preserve the original arguments object against
assignments to "arguments".

This change breaks the aliasing between parameters and arguments, and
temporarily makes the arguments object mirror behave the same in strict and
non-strict mode.

Committed: http://code.google.com/p/v8/source/detail?r=7240

[Kevin Millikin (Chromium), 2011-03-17 13:47:46]

http://codereview.chromium.org/6667076/diff/1/arguments/src/scopes.cc
File arguments/src/scopes.cc (left):

http://codereview.chromium.org/6667076/diff/1/arguments/src/scopes.cc#oldcode308
arguments/src/scopes.cc:308: variables_.Declare(this, name, Variable::VAR, true,
Variable::NORMAL);
I made these variables all have mode VAR, but I thought that this one used to be
CONST.

[Mads Ager (chromium), 2011-03-17 14:28:10]

LGTM.

http://codereview.chromium.org/6667076/diff/1/arguments/src/scopes.cc
File arguments/src/scopes.cc (right):

http://codereview.chromium.org/6667076/diff/1/arguments/src/scopes.cc#newcode862
arguments/src/scopes.cc:862: // (*). If we have a parameter named 'arguments', a
(new) value is
The (*) is not gone. :-)

[Kevin Millikin (Chromium), 2011-03-17 14:35:04]

http://codereview.chromium.org/6667076/diff/1/arguments/src/scopes.cc
File arguments/src/scopes.cc (right):

http://codereview.chromium.org/6667076/diff/1/arguments/src/scopes.cc#newcode862
arguments/src/scopes.cc:862: // (*). If we have a parameter named 'arguments', a
(new) value is
On 2011/03/17 14:28:10, Mads Ager wrote:
> The (*) is not gone. :-)

It is now.