Fix possible NPE in DirCacheCheckout

There was a chance that we hit a NPE which doing a checkout
with DirCacheCheckout when there is no HEAD (e.g. initial
checkout). This is fixed here.

Change-Id: Ie3b8cae21dcd90ba8352823ea94a700f8ee9221a
Signed-off-by: Christian Halstrick <christian.halstrick@sap.com>
1 file changed