Implement file_util::CountFilesCreatedAfter() for posix environments.

BUG=9833

Review URL: http://codereview.chromium.org/87003
Patch from Shinichiro Hamaji <[email protected]>.

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@14081 0039d316-1c4b-4281-b951-d872f2087c98
3 files changed