Fixed clearing of devicePath after UnmountDevice

UnmountDevice must not clear devicepath, because such devicePath
may come from node.status (e.g. on AWS) and subsequent MountDevice
operation (that may be already enqueued) needs it.

pkg/volume/testing/testing.go

@@ -250,6 +250,10 @@ type FakeVolumePlugin struct {
 	LimitKey               string
 	ProvisionDelaySeconds  int
 
+	// Add callbacks as needed
+	WaitForAttachHook func(spec *Spec, devicePath string, pod *v1.Pod, spectimeout time.Duration) (string, error)
+	UnmountDeviceHook func(globalMountPath string) error
+
 	Mounters             []*FakeVolume
 	Unmounters           []*FakeVolume
 	Attachers            []*FakeVolume
@@ -269,7 +273,10 @@ var _ DeviceMountableVolumePlugin = &FakeVolumePlugin{}
 var _ FSResizableVolumePlugin = &FakeVolumePlugin{}
 
 func (plugin *FakeVolumePlugin) getFakeVolume(list *[]*FakeVolume) *FakeVolume {
-	volume := &FakeVolume{}
+	volume := &FakeVolume{
+		WaitForAttachHook: plugin.WaitForAttachHook,
+		UnmountDeviceHook: plugin.UnmountDeviceHook,
+	}
 	*list = append(*list, volume)
 	return volume
 }
@@ -551,6 +558,10 @@ type FakeVolume struct {
 	Plugin  *FakeVolumePlugin
 	MetricsNil
 
+	// Add callbacks as needed
+	WaitForAttachHook func(spec *Spec, devicePath string, pod *v1.Pod, spectimeout time.Duration) (string, error)
+	UnmountDeviceHook func(globalMountPath string) error
+
 	SetUpCallCount              int
 	TearDownCallCount           int
 	AttachCallCount             int
@@ -724,6 +735,9 @@ func (fv *FakeVolume) WaitForAttach(spec *Spec, devicePath string, pod *v1.Pod,
 	fv.Lock()
 	defer fv.Unlock()
 	fv.WaitForAttachCallCount++
+	if fv.WaitForAttachHook != nil {
+		return fv.WaitForAttachHook(spec, devicePath, pod, spectimeout)
+	}
 	return "/dev/sdb", nil
 }
 
@@ -776,6 +790,9 @@ func (fv *FakeVolume) UnmountDevice(globalMountPath string) error {
 	fv.Lock()
 	defer fv.Unlock()
 	fv.UnmountDeviceCallCount++
+	if fv.UnmountDeviceHook != nil {
+		return fv.UnmountDeviceHook(globalMountPath)
+	}
 	return nil
 }