Merge pull request #65256 from liggitt/crd-schema-openapi

Automatic merge from submit-queue (batch tested with PRs 65256, 64236, 64919, 64879, 57932). 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>.

Fix CRD OpenAPI schema

fixes #65243
depends on https://github.com/kubernetes/kube-openapi/pull/84

without this PR, kubectl complains about creating this CRD with a validation schema (which worked in 1.10):
```yaml
apiVersion: apiextensions.k8s.io/v1beta1
kind: CustomResourceDefinition
metadata:
  name: resources.mygroup.example.com
spec:
  group: mygroup.example.com
  version: v1alpha1
  scope: Namespaced
  names:
    plural: resources
    singular: resource
    kind: Kind
    listKind: KindList
  validation:
    openAPIV3Schema:
      properties:
        spec:
          type: array
          items:
            type: number
```

> error: error validating "/Users/jliggitt/projects/snippets/crd/crd.yaml": error validating data: [ValidationError(CustomResourceDefinition.spec.validation.openAPIV3Schema.properties.spec.items): unknown field "type" in io.k8s.apiextensions-apiserver.pkg.apis.apiextensions.v1beta1.JSONSchemaPropsOrArray, ValidationError(CustomResourceDefinition.spec.validation.openAPIV3Schema.properties.spec.items): missing required field "Schema" in io.k8s.apiextensions-apiserver.pkg.apis.apiextensions.v1beta1.JSONSchemaPropsOrArray, ValidationError(CustomResourceDefinition.spec.validation.openAPIV3Schema.properties.spec.items): missing required field "JSONSchemas" in io.k8s.apiextensions-apiserver.pkg.apis.apiextensions.v1beta1.JSONSchemaPropsOrArray]; if you choose to ignore these errors, turn validation off with --validate=false

that is because the types used to serialize JSONSchema require custom marshaling/unmarshaling, and the OpenAPI generator was not informed of that, so it produced this:
```json
{
    "io.k8s.apiextensions-apiserver.pkg.apis.apiextensions.v1beta1.JSONSchemaPropsOrArray": {
    "description": "JSONSchemaPropsOrArray represents a value that can either be a JSONSchemaProps or an array of JSONSchemaProps. Mainly here for serialization purposes.",
    "required": [
     "Schema",
     "JSONSchemas"
    ],
    "properties": {
     "JSONSchemas": {
      "type": "array",
      "items": {
       "$ref": "#/definitions/io.k8s.apiextensions-apiserver.pkg.apis.apiextensions.v1beta1.JSONSchemaProps"
      }
     },
     "Schema": {
      "$ref": "#/definitions/io.k8s.apiextensions-apiserver.pkg.apis.apiextensions.v1beta1.JSONSchemaProps"
     }
    }
   }
}
```

OpenAPI isn't able to represent oneOf/anyOf types correctly currently. Until it can, we definitely shouldn't publish a schema containing required fields which aren't even part of the JSON serialization. This PR implements custom openapi type functions, which omit the properties/required/schema attributes for four specific JSONSchema types. This allows kubectl to continue creating these objects without complaining.

/sig api-machinery
/assign @sttts

```release-note
fixed incorrect OpenAPI schema for CustomResourceDefinition objects
```

Kubernetes-commit: ed6c8b7326bd1a1b845719f4bfb302073a18f03f

vendor/k8s.io/apimachinery/pkg/api/resource/quantity.go

@@ -69,11 +69,6 @@ import (
 //   1.5 will be serialized as "1500m"
 //   1.5Gi will be serialized as "1536Mi"
 //
-// NOTE: We reserve the right to amend this canonical format, perhaps to
-//   allow 1.5 to be canonical.
-// TODO: Remove above disclaimer after all bikeshedding about format is over,
-//   or after March 2015.
-//
 // Note that the quantity will NEVER be internally represented by a
 // floating point number. That is the whole point of this exercise.
 //
@@ -506,7 +501,7 @@ func (q *Quantity) Sign() int {
 	return q.i.Sign()
 }
 
-// AsScaled returns the current value, rounded up to the provided scale, and returns
+// AsScale returns the current value, rounded up to the provided scale, and returns
 // false if the scale resulted in a loss of precision.
 func (q *Quantity) AsScale(scale Scale) (CanonicalValue, bool) {
 	if q.d.Dec != nil {