The novel addition here is to not convert a checkout into an update when no
files were checked out. Also delete the directory to increase the chances of
success.

TEST=wait for google code to fail again
BUG=32783

Review URL: http://codereview.chromium.org/2858003

git-svn-id: svn://svn.chromium.org/chrome/trunk/tools/depot_tools@49788 0039d316-1c4b-4281-b951-d872f2087c98