Prevent compiling cpu_unittest on i386. This change prevents compiling cpu_unittest on 32-bit GCC since some builders does not compile with SSE support.
Prevent compiling cpu_unittest on i386.
This change prevents compiling cpu_unittest on 32-bit GCC since some builders does not compile with SSE support.

TBR=jiesun
BUG=none
TEST=fix build.
Review URL: http://codereview.chromium.org/6578017

git-svn-id: http://src.chromium.org/svn/trunk/src@75871 4ff67af0-8c30-449e-8e8b-ad334ec8d88c

Former-commit-id: 8225ccf522f53d77d12dffbeb718082ffb95a668
meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser