Merged r15303 into 3.18 branch.

MIPS: Fix Kraken gaussian blur test regression.

R=jkummerow@chromium.org
BUG=

Review URL: https://codereview.chromium.org/17569018

git-svn-id: https://v8.googlecode.com/svn/branches/3.18@15307 ce2b1a6d-e550-0410-aec6-3dcde31c8c00