Initialize elements pointer in BuildCloneShallowArray when allocation folding is turned off for arrays with lenght larger than zero.

BUG=
R=mvstanton@chromium.org

Review URL: https://codereview.chromium.org/240933003

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@20853 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This should make the NaCl build jobs green again.

BUG=
R=hpayer@chromium.org, jkummerow@chromium.org

Review URL: https://codereview.chromium.org/239333015

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@20854 ce2b1a6d-e550-0410-aec6-3dcde31c8c00