UPSTREAM: 62462: Private mount propagation

[jsafrane]

Introduce private mount propagation and make it default.

kubernetes/kubernetes#62462

[gnufied]

cc @liggitt

[jsafrane]

/assign @derekwaynecarr
for approval of node changes Please approve kubernetes/kubernetes#62633 too to pick it into 1.10.

@liggitt, please approve the API changes.

[liggitt]

/lgtm
/hold
hold for upstream 1.10 PR to merge

[derekwaynecarr]

/approve

note i just approved the upstream.

[openshift-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: derekwaynecarr, jsafrane

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• vendor/k8s.io/kubernetes/pkg/apis/core/OWNERS [derekwaynecarr]
• vendor/k8s.io/kubernetes/pkg/kubelet/OWNERS [derekwaynecarr]
• vendor/k8s.io/kubernetes/staging/src/k8s.io/api/OWNERS [derekwaynecarr]
• vendor/k8s.io/kubernetes/test/e2e/node/OWNERS [derekwaynecarr]

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[jsafrane]

/hold cancel

It was merged upstream into 1.10.x