Share /var/lib/kubernetes on startup

Kubelet makes sure that /var/lib/kubelet is rshared when it starts.
If not, it bind-mounts it with rshared propagation to containers
that mount volumes to /var/lib/kubelet can benefit from mount propagation.

pkg/util/removeall/removeall_test.go

@@ -66,6 +66,10 @@ func (mounter *fakeMounter) IsLikelyNotMountPoint(file string) (bool, error) {
 	return true, nil
 }
 
+func (mounter *fakeMounter) MakeRShared(path string) error {
+	return nil
+}
+
 func TestRemoveAllOneFilesystem(t *testing.T) {
 	tests := []struct {
 		name string