Extract volume relevant events reason

Extract volume relevant events reason and make them const

pkg/controller/volume/events/event.go

@@ -0,0 +1,32 @@
+/*
+Copyright 2017 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 events
+
+const (
+	// volume relevant event reasons
+	FailedBinding             = "FailedBinding"
+	VolumeMismatch            = "VolumeMismatch"
+	VolumeFailedRecycle       = "VolumeFailedRecycle"
+	VolumeRecycled            = "VolumeRecycled"
+	RecyclerPod               = "RecyclerPod"
+	VolumeDelete              = "VolumeDelete"
+	VolumeFailedDelete        = "VolumeFailedDelete"
+	ExternalProvisioning      = "ExternalProvisioning"
+	ProvisioningFailed        = "ProvisioningFailed"
+	ProvisioningCleanupFailed = "ProvisioningCleanupFailed"
+	ProvisioningSucceeded     = "ProvisioningSucceeded"
+)