Version 3.26.31.12 (merged r22616, r22617)

In GrowMode, force the value to the right representation to avoid deopts between storing the length and storing the value.

Smi arrays are only guaranteed to be initialized in non-holey case

BUG=16459193
LOG=y
R=ishell@chromium.org

Review URL: https://codereview.chromium.org/430103002

git-svn-id: https://v8.googlecode.com/svn/branches/3.26@22739 ce2b1a6d-e550-0410-aec6-3dcde31c8c00