Fix daemon command proxy.

Signed-off-by: Daniel Nephin <dnephin@docker.com>

daemon_unit_test.go

@@ -0,0 +1,30 @@
+// +build daemon
+
+package main
+
+import (
+	"testing"
+
+	"github.com/docker/docker/pkg/testutil/assert"
+	"github.com/spf13/cobra"
+)
+
+func stubRun(cmd *cobra.Command, args []string) error {
+	return nil
+}
+
+func TestDaemonCommandHelp(t *testing.T) {
+	cmd := newDaemonCommand()
+	cmd.RunE = stubRun
+	cmd.SetArgs([]string{"--help"})
+	err := cmd.Execute()
+	assert.NilError(t, err)
+}
+
+func TestDaemonCommand(t *testing.T) {
+	cmd := newDaemonCommand()
+	cmd.RunE = stubRun
+	cmd.SetArgs([]string{"--containerd", "/foo"})
+	err := cmd.Execute()
+	assert.NilError(t, err)
+}