Declaration of const lookup slots would trigger an assertion if there was a
setter somewhere in the prototype chain, and that setter was shadowed by a
non-readonly data property also in the prototype chain.

R=ager@chromium.org
BUG=
TEST=

Review URL: http://codereview.chromium.org/7324048

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@8602 ce2b1a6d-e550-0410-aec6-3dcde31c8c00