Merge pull request #54154 from mtaufen/deprecate-enable-custom-metrics

Automatic merge from submit-queue (batch tested with PRs 54154, 54192). If you want to cherry-pick this change to another branch, please follow the instructions <a href="https://github.com/kubernetes/community/blob/master/contributors/devel/cherry-picks.md">here</a>.

Move --enable-cusom-metrics to KubeletFlags and mark it deprecated

With respect to https://github.com/kubernetes/kubernetes/pull/53833#issuecomment-336890235, EnableCustomMetrics should be marked deprecated and should not remain in the KubeletConfiguration struct. 

Broader issue: https://github.com/kubernetes/features/issues/281

```release-note
The Kubelet's --enable-custom-metrics flag is now marked deprecated.
```

pkg/kubelet/apis/kubeletconfig/types.go

@@ -252,8 +252,6 @@ type KubeletConfiguration struct {
 	SerializeImagePulls bool
 	// nodeLabels to add when registering the node in the cluster.
 	NodeLabels map[string]string
-	// enable gathering custom metrics.
-	EnableCustomMetrics bool
 	// Comma-delimited list of hard eviction expressions.  For example, 'memory.available<300Mi'.
 	// +optional
 	EvictionHard string

pkg/kubelet/apis/kubeletconfig/v1alpha1/types.go

@@ -244,8 +244,6 @@ type KubeletConfiguration struct {
 	SerializeImagePulls *bool `json:"serializeImagePulls"`
 	// nodeLabels to add when registering the node in the cluster.
 	NodeLabels map[string]string `json:"nodeLabels"`
-	// enable gathering custom metrics.
-	EnableCustomMetrics bool `json:"enableCustomMetrics"`
 	// Comma-delimited list of hard eviction expressions.  For example, 'memory.available<300Mi'.
 	EvictionHard *string `json:"evictionHard"`
 	// Comma-delimited list of soft eviction expressions.  For example, 'memory.available<300Mi'.

pkg/kubelet/apis/kubeletconfig/v1alpha1/zz_generated.conversion.go

@@ -244,7 +244,6 @@ func autoConvert_v1alpha1_KubeletConfiguration_To_kubeletconfig_KubeletConfigura
 		return err
 	}
 	out.NodeLabels = *(*map[string]string)(unsafe.Pointer(&in.NodeLabels))
-	out.EnableCustomMetrics = in.EnableCustomMetrics
 	if err := v1.Convert_Pointer_string_To_string(&in.EvictionHard, &out.EvictionHard, s); err != nil {
 		return err
 	}
@@ -385,7 +384,6 @@ func autoConvert_kubeletconfig_KubeletConfiguration_To_v1alpha1_KubeletConfigura
 		return err
 	}
 	out.NodeLabels = *(*map[string]string)(unsafe.Pointer(&in.NodeLabels))
-	out.EnableCustomMetrics = in.EnableCustomMetrics
 	if err := v1.Convert_string_To_Pointer_string(&in.EvictionHard, &out.EvictionHard, s); err != nil {
 		return err
 	}

pkg/kubemark/hollow_kubelet.go

@@ -144,7 +144,6 @@ func GetHollowKubeletConfig(
 	c.CPUCFSQuota = true
 	c.RuntimeCgroups = ""
 	c.EnableControllerAttachDetach = false
-	c.EnableCustomMetrics = false
 	c.EnableDebuggingHandlers = true
 	c.EnableServer = true
 	c.CgroupsPerQOS = false