This will reduce the approval load for the top level tree owners

Automatic merge from submit-queue

Increase default value of apps/v1beta2 DeploymentSpec.RevisionHistoryLimit to 10

**What this PR does / why we need it**:

All controllers that use the `RevisionHistoryLimit` field have a default value of 10 for the field, except for `Deployment`, which has a default of 2. We should increase it to 10 for consistency on its default value across controllers.

**Which issue this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close that issue when PR gets merged)*: fixes #49913

**Special notes for your reviewer**:
/cc @janetkuo @foxish @liyinan926

**Release note**:

```release-note
Increase default value of apps/v1beta2 DeploymentSpec.RevisionHistoryLimit to 10
```

Automatic merge from submit-queue

Fix incorrect owner in OWNERS

**What this PR does / why we need it**:
typo: yuyuhong --> yujuhong

**Which issue this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close that issue when PR gets merged)*: fixes #
https://github.com/kubernetes/kubernetes/issues/50048#issuecomment-319846621

**Special notes for your reviewer**:
/assign @yujuhong 
I don't know whether you can approve this PR or not in such case 😄 

**Release note**:

```release-note
NONE
```

Automatic merge from submit-queue

Moves left networking e2e tests to test/e2e/network

**What this PR does / why we need it**:
#48784 forgot to move some networking e2e tests. This PR moves them.

It also move the networking tests from within `test/e2e/common/networking.go` to  `test/e2e/network/networking.go`

**Which issue this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close that issue when PR gets merged)*: fixes #
Associated PR #48784
Umbrella issue #49161

**Special notes for your reviewer**:
/assign @wojtek-t @bowei 

**Release note**:

```release-note
NONE
```

Automatic merge from submit-queue

fix typo in staging/src/k8s.io/apiserver/pkg/server/config.go

**What this PR does / why we need it**: Fix a typo `It's members are sorted roughly in order of importance for composers.` in `staging/src/k8s.io/apiserver/pkg/server/config.go`.

**Which issue this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close that issue when PR gets merged)*: fixes #

**Special notes for your reviewer**:

**Release note**:

`NONE`

Automatic merge from submit-queue

Moved node condition check into Predicats.

**Which issue this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close that issue when PR gets merged)*: partially fixes #42001 

**Release note**:

```release-note
None
```

Automatic merge from submit-queue

Remove remaining traces of go2idl

Automatic merge from submit-queue

Add --feature-gate flags to kubeadm

**What this PR does / why we need it**:

Adds `--feature-gates` in similar manner to other `cmd` binaries

**Which issue this PR fixes** 

https://github.com/kubernetes/kubeadm/issues/323

**Special notes for your reviewer**:

This results in a lot of probably unnecessary feature flags. I'm guessing a lot of kubeadm users will be confused when they see:

```
Flags:
      --feature-gates mapStringBool   A set of key=value pairs that describe feature gates for alpha/experimental features. Options are:
APIResponseCompression=true|false (ALPHA - default=false)
Accelerators=true|false (ALPHA - default=false)
AdvancedAuditing=true|false (ALPHA - default=false)
AllAlpha=true|false (ALPHA - default=false)
AllowExtTrafficLocalEndpoints=true|false (default=true)
AppArmor=true|false (BETA - default=true)
DebugContainers=true|false (ALPHA - default=false)
DynamicKubeletConfig=true|false (ALPHA - default=false)
DynamicVolumeProvisioning=true|false (ALPHA - default=true)
ExperimentalCriticalPodAnnotation=true|false (ALPHA - default=false)
ExperimentalHostUserNamespaceDefaulting=true|false (BETA - default=false)
LocalStorageCapacityIsolation=true|false (ALPHA - default=false)
PersistentLocalVolumes=true|false (ALPHA - default=false)
PodPriority=true|false (ALPHA - default=false)
RotateKubeletClientCertificate=true|false (ALPHA - default=false)
RotateKubeletServerCertificate=true|false (ALPHA - default=false)
StreamingProxyRedirects=true|false (BETA - default=true)
TaintBasedEvictions=true|false (ALPHA - default=false)
  -h, --help                          help for kubeadm
```

However the feature flags used in the core pkg is global, so I don't think it can be overriden. So we have a few options:

1. Allow these flags for kubeadm
2. Refactor feature pkg to allow granular features
3. Roll our own feature gating for kubeadm

/cc @luxas

Automatic merge from submit-queue

Switch from package syscall to golang.org/x/sys/unix

**What this PR does / why we need it**:

The syscall package is locked down and the comment in https://github.com/golang/go/blob/master/src/syscall/syscall.go#L21-L24 advises to switch code to use the corresponding package from golang.org/x/sys. This PR does so and replaces usage of package syscall with package golang.org/x/sys/unix where applicable. This will also allow to get updates and fixes
without having to use a new go version.

In order to get the latest functionality, golang.org/x/sys/ is re-vendored. This also allows to use Eventfd() from this package instead of calling the eventfd() C function.

**Special notes for your reviewer**:

This follows previous works in other Go projects, see e.g. moby/moby#33399, cilium/cilium#588

**Release note**:

```release-note
NONE
```

Automatic merge from submit-queue

Add missing ugorji codecs for auth/v1, settings/v1alphav1 and storage/v1

Automatic merge from submit-queue

Fix comment of request.go

**What this PR does / why we need it**:
Fix comment of request.go

**Which issue this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close that issue when PR gets merged)*: fixes #

**Special notes for your reviewer**:

**Release note**:

```release-note
NONE
```

Automatic merge from submit-queue

client-gen: don't ignore nil clientsets

Closes https://github.com/kubernetes/client-go/issues/240

When a clientset is nil, fail fast instead of returning a nil value as an interface.

/cc @kubernetes/sig-api-machinery-pr-reviews

Automatic merge from submit-queue (batch tested with PRs 49916, 50050)

GCE: Fix bug by correctly cast port to string

Code is incorrectly casting a port to a string, causing the diff-expression to always return true. 

**What this PR does / why we need it**:
Fixes #50049

**Special notes for your reviewer**:
/assign @MrHohn 

**Release note**:
```release-note
NONE
```

Automatic merge from submit-queue (batch tested with PRs 49916, 50050)

Update images used in the node e2e benchmark tests

Ref: https://github.com/kubernetes/kubernetes/issues/42926

- Update the cosbeta image since the new version contains a 'du' command fix that affects Docker performance.
- Add the coreos and ubuntu image that run Docker 1.12.6 so that we will have more data to compare.

**Release note**:
```
None
```

Automatic merge from submit-queue (batch tested with PRs 48365, 49902, 49808, 48722, 47045)

Improve shared informer notification dispatching

**What this PR does / why we need it**:
Locks and channels don't play well together. This is an attempt to remove locks and only use channels in shared informer. It looks much cleaner to me.

**Release note**:
```release-note
NONE
```

@deads2k @ncdc

Automatic merge from submit-queue (batch tested with PRs 48365, 49902, 49808, 48722, 47045)

Upgrade fluentd-elasticsearch addon to Elasticsearch/Kibana 5.5

This is a patch to upgrade the fluentd-elasticsearch addon to Elasticsearch/Kibana 5.5. Please provide feedback!

```release-notes
* Upgrade Elasticsearch/Kibana to 5.5.1 in fluentd-elasticsearch addon
* Switch to basing our image of Elasticsearch in fluentd-elasticsearch addon off the official one
* Switch to the official image of Kibana in fluentd-elasticsearch addon
* Use StatefulSet for Elasticsearch instead of ReplicationController, with persistent volume claims
* Require authenticating towards Elasticsearch, as Elasticsearch 5.5 by default requires basic authentication
```

Automatic merge from submit-queue (batch tested with PRs 48365, 49902, 49808, 48722, 47045)

Add admission controller API to runtime config and externalize ADMISSION_CONTROL

**What this PR does / why we need it**:

Enable the dynamic admission controller registration API by
adding "admissionregistration.k8s.io/v1alpha1" to --runtime-config
to fix problems when starting up local-up-cluster. Also make sure
ADMISSION_CONTROL can be specified externally.

**Which issue this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close that issue when PR gets merged)*: fixes #

Fixes #47385

**Special notes for your reviewer**:

**Release note**:

```release-note
NONE
```

Automatic merge from submit-queue (batch tested with PRs 48365, 49902, 49808, 48722, 47045)

Allow update to GC fields for RBAC resources

This change makes it so that no escalation check is performed when updating only the garbage collector fields (owner references and finalizers) of RBAC resources.  This allows the garbage collector to delete roles that grant permissions such as "create", which it will never have.
Signed-off-by: Monis Khan <mkhan@redhat.com>

@kubernetes/sig-auth-api-reviews 

```release-note
NONE
```

Automatic merge from submit-queue (batch tested with PRs 48365, 49902, 49808, 48722, 47045)

Rebase hyperkube image on debian-hyperkube-base, based on debian-base.

**What this PR does / why we need it**: saves all of the hyperkube image dependencies in a cacheable base image, rather than downloading them for every build (which is slow and flaky).

This way, at build time, we only need to pull down the hyperkube base image and add the hyperkube binary.

I've additionally based the base image on `debian-base` instead of `debian`, though we amusing end up reinstalling a bunch of the things we removed in `debian-base`.

**Which issue this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close that issue when PR gets merged)*: fixes #35058, at least partially

**Special notes for your reviewer**: I'm increasingly convinced that the hyperkube image is a bad pattern, as this image carries the superset of dependencies anyone might need, rather than the limited set of dependencies one needs. hyperkube really needs a proper owner.

**Release note**:

```release-note
```

/assign @timstclair @luxas @philips @nikhiljindal 
cc @kubernetes/sig-release-pr-reviews

Automatic merge from submit-queue

remove dead log handler and increase verbosity

We had a handler that no one was using and this bumps the verbosity slightly (2->3) to reduce noise at 2.

Automatic merge from submit-queue (batch tested with PRs 50000, 49954, 49943, 50018, 49607)

change apps/v1beta2 StatefulSet observedGeneration from a pointer to an int for consistency

**What this PR does / why we need it**:
change the StatefulSet observedGeneration from a pointer to an int for consistency

**Which issue this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close that issue when PR gets merged)*: fixes #49623
xref #49135

**Special notes for your reviewer**:
/cc @janetkuo @foxish @kow3ns 

**Release note**:

```release-note
change apps/v1beta2 StatefulSet observedGeneration (optional field) from a pointer to an int for consistency
```

Automatic merge from submit-queue (batch tested with PRs 50000, 49954, 49943, 50018, 49607)

Remove extraneous white space

**What this PR does / why we need it**:

Output from command `kubectl delete --help` contains extraneous whitespace. While we are at it, paragraph in multi-paragraph section has shorter line lengths, text looks better if all paragraphs have similar line lengths.

**Which issue this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close that issue when PR gets merged)*: fixes #

**Special notes for your reviewer**:

White space only. This PR is outward facing but so trivial I don't think it needs a release note. I'm new around here, if this assumption is incorrect please tell me. Thanks.

**Release note**:

```release-note
NONE
```

Automatic merge from submit-queue (batch tested with PRs 50000, 49954, 49943, 50018, 49607)

Add [sig-autoscaling] prefix to autoscaling e2e tests

**What this PR does / why we need it**:
Add [sig-autoscaling] prefix to autoscaling e2e tests

**Which issue this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close that issue when PR gets merged)*: fixes #
Umbrella issue #49161

**Special notes for your reviewer**:

**Release note**:

```release-note
NONE
```

Automatic merge from submit-queue (batch tested with PRs 50000, 49954, 49943, 50018, 49607)

Update the DeleteReplicaSet in rs_util.go to use server side reaper

**What this PR does / why we need it**:
fix #47832
**Which issue this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close that issue when PR gets merged)*: fixes #47832

**Special notes for your reviewer**:

**Release note**:

```
None
```

Automatic merge from submit-queue (batch tested with PRs 50000, 49954, 49943, 50018, 49607)

Add [sig-scalability] prefix to scalability e2e tests

**What this PR does / why we need it**:
Add [sig-scalability] prefix to scalability e2e tests

**Which issue this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close that issue when PR gets merged)*: fixes #
Umbrella issue #49161

**Special notes for your reviewer**:

**Release note**:

```release-note
NONE
```

Automatic merge from submit-queue (batch tested with PRs 49237, 49656, 49980, 49841, 49899)

certificate manager: close existing client conns once cert rotates

After the kubelet rotates its client cert, it will keep connections to the API server open indefinitely, causing it to use its old credentials instead of the new certs. Because the API server authenticates client certs at the time of the request, and not the handshake, this could cause the kubelet to start hitting auth failures even if it rotated its certificate to a new, valid one.
    
When the kubelet rotates its cert, close down existing connections to force a new TLS handshake.

Ref https://github.com/kubernetes/features/issues/266
Updates https://github.com/kubernetes-incubator/bootkube/pull/663

```release-note
After a kubelet rotates its client cert, it now closes its connections to the API server to force a handshake using the new cert. Previously, the kubelet could keep its existing connection open, even if the cert used for that connection was expired and rejected by the API server.
```

/cc @kubernetes/sig-auth-bugs 
/assign @jcbsmpsn @mikedanese

Automatic merge from submit-queue (batch tested with PRs 49237, 49656, 49980, 49841, 49899)

[Bug Fix] Set NodeOODCondition to false

fixes #49839, which was introduced by #48846

This PR makes the kubelet set NodeOODCondition to false, so that the scheduler and other controllers do not consider the node to be unschedulable.

/assign @vishh 
/sig node
/release-note-none

Automatic merge from submit-queue (batch tested with PRs 49237, 49656, 49980, 49841, 49899)

GC shouldn't send empty patch

The scope of the `if` statement was wrong, causing GC to sometimes send empty patch.

Found this bug while investigating https://github.com/kubernetes/kubernetes/issues/49966.

Automatic merge from submit-queue (batch tested with PRs 49237, 49656, 49980, 49841, 49899)

make admission tolerate object without objectmeta for errors

Not all object have ObjectMeta (see SARs for instance).  Admission should tolerate this condition without giving meaningless errors.

@derekwaynecarr ptal
@php-coder fyi

Automatic merge from submit-queue (batch tested with PRs 49237, 49656, 49980, 49841, 49899)

Improve our Instance Metadata coverage in Azure.

Automatic merge from submit-queue (batch tested with PRs 49989, 49806, 49649, 49412, 49512)

Add some logs to certificate rotation

```release-note
NONE
```

Automatic merge from submit-queue (batch tested with PRs 49989, 49806, 49649, 49412, 49512)

This adds an etcd health check endpoint to kube-apiserver

addressing https://github.com/kubernetes/kubernetes/issues/48215.

**What this PR does / why we need it**:
This ensures kube-apiserver `/healthz` endpoint fails whenever connectivity cannot be established to etcd, also ensures the etcd preflight checks works with unix sockets

**Which issue this PR fixes**: fixes #48215

**Special notes for your reviewer**:
This PR does not use the etcd client directly as the client object is wrapped behind the storage interface and not exposed directly for use, so I decided to reuse what's being done in the preflight. So this will only check fail for connectivity and not etcd auth related problems. I did not write tests for the endpoint because I couldn't find examples that I could follow for writing tests for healthz related endpoints, I'll be willing to write those tests if someone can point me at a relevant one.

**Release note**:
```release-note
Add etcd connectivity endpoint to healthz
```

@deads2k please help review, thanks!

Automatic merge from submit-queue (batch tested with PRs 49989, 49806, 49649, 49412, 49512)

Use existing k8s binaries and images on disk when they are preloaded to gce cos image.

**What this PR does / why we need it**:
This change is to accelerate K8S startup time on gce when k8s tarballs and images are already preloaded in VM image, by skipping the downloading, extracting and file transfer steps.

**Which issue this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close that issue when PR gets merged)*: fixes #

**Special notes for your reviewer**:

**Release note**:

```release-note
NONE
```

Automatic merge from submit-queue (batch tested with PRs 49989, 49806, 49649, 49412, 49512)

Update repo-infra and rules_go Bazel workspace dependencies

**What this PR does / why we need it**: bumping the `repo-infra` dependency gets us https://github.com/kubernetes/repo-infra/pull/25, which hopefully fixes the `gsutil -m rsync` flakiness in the `pull-kubernetes-e2e-gce-bazel` job, and https://github.com/kubernetes/repo-infra/pull/26, which lets us bump the `rules_go` dependency.

Bumping the `rules_go` dependency fixes the build on bazel 0.5.3+, gives us race detector support, and probably a bunch of other features, too. It's also a prerequisite for switching to gazelle (#47558).

**Release note**:

```release-note
NONE
```

/assign @spxtr @mikedanese