Revert "libyuv: Include foo_posix.cc in the gn build, like it's done in the gyp build."

BUG=496928
R=thakis@chromium.org

Review URL: https://webrtc-codereview.appspot.com/58399004

git-svn-id: http://libyuv.googlecode.com/svn/trunk@1424 16f28f9a-4ce2-e073-06de-1de4eb20be90
1 file changed