CrOS: Update Chromite pin.
CrOS: Update Chromite pin.

Update ChromeOS Chromite pins.
- [master]
  b2d341616f5043863449ad74d8e4fb06fe9a9b58 =>
     479596311512415c700a2a46eb6a43b9362586df

TBR=bradnelson@google.com

Review URL: https://codereview.chromium.org/1409933005

git-svn-id: 239fca9b83025a0b6f823aeeca02ba5be3d9fd76@297285 0039d316-1c4b-4281-b951-d872f2087c98

eunchong/build,eunchong/build,eunchong/build,eunchong/build