Introduce a poor man's version of STL's bitset.
Introduce a poor man's version of STL's bitset.

Used in a separate upcoming patch...
Review URL: http://codereview.chromium.org/7472029

git-svn-id: b158db1e4b4ab85d4c9e510fdef4b1e8c614b15b@8715 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

UniversalFuture/moosh,UniversalFuture/moosh,UniversalFuture/moosh,UniversalFuture/moosh