CPP: Don't add GCC flags and don't link with pthread on WIN32.
CPP: Don't add GCC flags and don't link with pthread on WIN32.

Review URL: http://codereview.appspot.com/5302049

git-svn-id: 8a271f26b5f22ddf2239749c3695dd2f7343a890@370 ee073f10-1060-11df-b6a4-87a95322a99c

dpocock/libphonenumber-from-svn-mirror,dpocock/libphonenumber-from-svn-mirror,dpocock/libphonenumber-from-svn-mirror,dpocock/libphonenumber-from-svn-mirror