Function to compute the total size of the files in a directory

We need this for the diagnostic mode but it can be used by others.
Did not see test for GetFileSize() so added them

BUG=none
TEST=ut included


Review URL: http://codereview.chromium.org/1220001

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@42540 0039d316-1c4b-4281-b951-d872f2087c98


CrOS-Libchrome-Original-Commit: c2c132c637874d6d3104293791b15b38da58bfc9
3 files changed
tree: c974075e754f5d2cd0d79014a30a5e407719d095
  1. base/
  2. build/
  3. ipc/
  4. testing/