Remove use of ToLower to reduce memory copies

RequestInfo always have lowercase strings in it, so no need to
lower case or casefold compare anything.

Signed-off-by: Simo Sorce <[email protected]>

Author: simo5

pkg/authorization/authorizer/personal_subjectaccessreview.go

@@ -4,7 +4,6 @@ import (
 	"bytes"
 	"io/ioutil"
 	"net/http"
-	"strings"
 
 	"k8s.io/apimachinery/pkg/runtime/schema"
 	"k8s.io/apiserver/pkg/endpoints/request"
@@ -42,10 +41,10 @@ func (a *personalSARRequestInfoResolver) NewRequestInfo(req *http.Request) (*req
 	case len(requestInfo.Subresource) != 0:
 		return requestInfo, nil
 
-	case strings.ToLower(requestInfo.Verb) != "create":
+	case requestInfo.Verb != "create":
 		return requestInfo, nil
 
-	case strings.ToLower(requestInfo.Resource) != "subjectaccessreviews" && strings.ToLower(requestInfo.Resource) != "localsubjectaccessreviews":
+	case requestInfo.Resource != "subjectaccessreviews" && requestInfo.Resource != "localsubjectaccessreviews":
 		return requestInfo, nil
 	}
 
@@ -76,7 +75,7 @@ func isPersonalAccessReviewFromRequest(req *http.Request, requestInfo *request.R
 	req.Body = ioutil.NopCloser(bytes.NewBuffer(body))
 
 	defaultGVK := schema.GroupVersionKind{Version: requestInfo.APIVersion, Group: requestInfo.APIGroup}
-	switch strings.ToLower(requestInfo.Resource) {
+	switch requestInfo.Resource {
 	case "subjectaccessreviews":
 		defaultGVK.Kind = "SubjectAccessReview"
 	case "localsubjectaccessreviews":