Add atomics implementation for ThreadSanitizer v2 (https://sites.google.com/a/chromium.org/dev/developers/testing/threadsanitizer-tsan-v2)

BUG=128314

Review URL: https://chromiumcodereview.appspot.com/10965035
Patch from Alexander Potapenko <glider@chromium.org>.

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12953 ce2b1a6d-e550-0410-aec6-3dcde31c8c00