Re-apply r3153 with a fix for issue 490. Except for the change in line 1756 and the added test this change is identical to http://codereview.chromium.org/342015.

BUG=490
TEST=test/mjsunit/regress/regress-490.js
Review URL: http://codereview.chromium.org/341064

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@3197 ce2b1a6d-e550-0410-aec6-3dcde31c8c00