Fix Array index dehoisting.

BUG=264203
TEST=test/mjsunit/regress/regress-264203
R=danno@chromium.org

Review URL: https://chromiumcodereview.appspot.com/22314012

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@16082 ce2b1a6d-e550-0410-aec6-3dcde31c8c00