BUG=303
TESTED=cl /c /TC /Iinclude source/format_conversion.cc
R=tpsiaki@google.com

Review URL: https://webrtc-codereview.appspot.com/10709004

git-svn-id: http://libyuv.googlecode.com/svn/trunk@990 16f28f9a-4ce2-e073-06de-1de4eb20be90