* ip-masq-agent is now on by default for GCE ([#47794](https://github.com/kubernetes/kubernetes/pull/47794), [@dnardo](https://github.com/dnardo))

  * Add ip-masq-agent addon to the addons folder which is used in GCE if `--non-masquerade-cidr` is set to 0/0 ([#46038](https://github.com/kubernetes/kubernetes/pull/46038), [@dnardo](https://github.com/dnardo))

- kubeadm: `kubeadm upgrade node` now supports `addon` and `post-upgrade` phases. Users can use `kubeadm upgrade node phase addon` to execute the addon upgrade, or use `kubeadm upgrade node --skip-phases addon` to skip the addon upgrade. If you were previously skipping an addon subphase on `kubeadm init` you should now skip the same addon when calling `kubeadm upgrade apply` and `kubeadm upgrade node`. Currently, the `post-upgrade` phase is...

  - ip-mask-agent addon starts to use the label `node.kubernetes.io/masq-agent-ds-ready` instead of `beta.kubernetes.io/masq-agent-ds-ready` as its node selector.
  - kube-proxy addon starts to use the label `node.kubernetes.io/kube-proxy-ds-ready` instead of `beta.kubernetes.io/kube-proxy-ds-ready` as its node selector.

### Other notable changes

* Trusty: Update heapster manifest handling code ([#23434](https://github.com/kubernetes/kubernetes/pull/23434), [@andyzheng0831](https://github.com/andyzheng0831))
* Support addon Deployments, make heapster a deployment with a nanny. ([#22893](https://github.com/kubernetes/kubernetes/pull/22893), [@Q-Lee](https://github.com/Q-Lee))

* Update cluster-proportional-autoscaler, etcd-empty-dir-cleanup, fluentd-gcp, and kube-addon-manager addons with refreshed base images containing fixes for CVE-2015-8271, CVE-2016-7543, CVE-2016-9841, CVE-2016-9843, CVE-2017-1000366, CVE-2017-2616, and CVE-2017-7507. ([#48011](https://github.com/kubernetes/kubernetes/pull/48011), [@ixdy](https://github.com/ixdy))...

* Unmount operation should not fail if volume is already unmounted ([#38547](https://github.com/kubernetes/kubernetes/pull/38547), [@rkouj](https://github.com/rkouj))
* Updates base image used for `kube-addon-manager` to latest `python:2.7-slim` and embedded `kubectl` to `v1.3.10`. No functionality changes expected. ([#42842](https://github.com/kubernetes/kubernetes/pull/42842), [@ixdy](https://github.com/ixdy))

* Add generic NoSchedule toleration to fluentd in gcp config. ([#48182](https://github.com/kubernetes/kubernetes/pull/48182), [@gmarek](https://github.com/gmarek))
* Update cluster-proportional-autoscaler, fluentd-gcp, and kube-addon-manager, and kube-dns addons with refreshed base images containing fixes for CVE-2016-9841, CVE-2016-9843, CVE-2017-2616, and CVE-2017-6512. ([#47454](https://github.com/kubernetes/kubernetes/pull/47454), [@ixdy](https://github.com/ixdy))

- Update crictl to v1.16.1. ([#82856](https://github.com/kubernetes/kubernetes/pull/82856), [@Random-Liu](https://github.com/Random-Liu))
- Bump addon-resizer to 1.8.7 to fix issues with using deprecated extensions APIs ([#85864](https://github.com/kubernetes/kubernetes/pull/85864), [@liggitt](https://github.com/liggitt))

- Kubeadm: added support for the flag `--print-manifest` to the addon phases `kube-proxy` and `coredns` of `kubeadm init phase addon`. If this flag is `usedkubeadm` will not apply a given addon and instead print to the terminal the API objects that will be applied. ([#109995](https://github.com/kubernetes/kubernetes/pull/109995), [@wangyysde](https://github.com/wangyysde))

#### add-ons:
- Remove cluster-monitoring addon ([#85512](https://github.com/kubernetes/kubernetes/pull/85512), [@serathius](https://github.com/serathius)) [SIG Cluster Lifecycle, Instrumentation, Scalability and Testing]

#### kube-scheduler: