Expand VPD initial_locale to a list of locales. Use the expanded VPD initial_locale on the OOBE.

Let's have device "most relevant" locales to be the first ones in the list
of locales at OOBE. To store "most relevant" list we expand VPD initial_locale
to contain list of locales.

BUG=334495, 334509
TEST=manual

Review URL: https://codereview.chromium.org/144363006

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@248241 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 248241