* Change the default kubeadm bootstrap token TTL from infinite to 24 hours. This is a breaking change. If you require the old behavior, use `kubeadm init --token-ttl 0` / `kubeadm token create --ttl 0`. ([#48783](https://github.com/kubernetes/kubernetes/pull/48783), [@mattmoyer](https://github.com/mattmoyer))

### Other notable changes

Some upgrade methods might upgrade etcd from 3.0 to 3.1 automatically when you upgrade from Kubernetes 1.8, unless you specify otherwise. Because [etcd does not support downgrading](https://coreos.com/etcd/docs/latest/upgrades/upgrade_3_1.html), you'll need to either remain on etcd 3.1 or restore from a backup if you want to downgrade back to Kubernetes 1.8.

## Introduction to 1.9.0

pkg go/types, type TypeName struct
pkg go/types, type Var struct
pkg go/types, var Typ []*Basic
pkg go/types, var Universe *Scope
pkg go/types, var Unsafe *Package
pkg html/template, method (*Template) Option(...string) *Template
pkg image, const YCbCrSubsampleRatio410 = 5
pkg image, const YCbCrSubsampleRatio410 YCbCrSubsampleRatio
pkg image, const YCbCrSubsampleRatio411 = 4

 [major_versions]: https://jakewharton.com/java-interoperability-policy-for-major-version-updates/
 [maven_provided]: https://maven.apache.org/guides/introduction/introduction-to-dependency-mechanism.html
 [nginx_959]: https://trac.nginx.org/nginx/ticket/959
 [obsolete_apache_client]: https://gist.github.com/swankjesse/09721f72039e3a46cf50f94323deb82d

			wantResult: `{"_1":-3}`,
		},
		// Examples from https://docs.aws.amazon.com/AmazonS3/latest/userguide/s3-glacier-select-sql-reference-date.html#s3-glacier-select-sql-reference-date-diff
		{
			name:       "date_diff_year",
			query:      `SELECT date_diff(year, '2010-01-01T', '2011-01-01T') FROM S3Object LIMIT 1`,
			wantResult: `{"_1":1}`,
		},
		{

// APIErrorCode type of error status.
type APIErrorCode int

//go:generate stringer -type=APIErrorCode -trimprefix=Err $GOFILE

// Error codes, non exhaustive list - http://docs.aws.amazon.com/AmazonS3/latest/API/ErrorResponses.html
const (
	ErrNone APIErrorCode = iota
	ErrAccessDenied
	ErrBadDigest
	ErrEntityTooSmall
	ErrEntityTooLarge
	ErrPolicyTooLarge
	ErrIncompleteBody
	ErrInternalError
	ErrInvalidAccessKeyID

See $GOROOT/cmd/cgo/internal/teststdio and $GOROOT/misc/cgo/gmp for examples. See
"C? Go? Cgo!" for an introduction to using cgo:
https://golang.org/doc/articles/c_go_cgo.html.

CFLAGS, CPPFLAGS, CXXFLAGS, FFLAGS and LDFLAGS may be defined with pseudo
#cgo directives within these comments to tweak the behavior of the C, C++
or Fortran compiler. Values defined in multiple directives are concatenated

## Changelog since v1.11.0

### Action Required

- github.com/opencontainers/runc: [v1.0.1 → v1.0.2](https://github.com/opencontainers/runc/compare/v1.0.1...v1.0.2)
- github.com/pelletier/go-toml: [v1.2.0 → v1.9.3](https://github.com/pelletier/go-toml/compare/v1.2.0...v1.9.3)
- github.com/prometheus/common: [v0.26.0 → v0.28.0](https://github.com/prometheus/common/compare/v0.26.0...v0.28.0)

	return req, err
}

// preSignV4 presign the request, in accordance with
// http://docs.aws.amazon.com/AmazonS3/latest/API/sigv4-query-string-auth.html.
func preSignV4(req *http.Request, accessKeyID, secretAccessKey string, expires int64) error {
	// Presign is not needed for anonymous credentials.
	if accessKeyID == "" || secretAccessKey == "" {