fix golint issues for pkg/volume/empty_dir

pkg/volume/emptydir/empty_dir_unsupported.go

@@ -0,0 +1,33 @@
+// +build !linux
+
+/*
+Copyright 2015 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package emptydir
+
+import (
+	"k8s.io/api/core/v1"
+	"k8s.io/kubernetes/pkg/util/mount"
+)
+
+// realMountDetector pretends to implement mediumer.
+type realMountDetector struct {
+	mounter mount.Interface
+}
+
+func (m *realMountDetector) GetMountMedium(path string) (v1.StorageMedium, bool, error) {
+	return v1.StorageMediumDefault, false, nil
+}