introduced in http://src.chromium.org/viewvc/chrome?view=rev&revision=20990

It was intended for the tarball generation script,
but there was a better and simpler way.

BUG=80549
Review URL: http://codereview.chromium.org/6883263

git-svn-id: svn://svn.chromium.org/chrome/trunk/tools/depot_tools@83708 0039d316-1c4b-4281-b951-d872f2087c98