vendor: update buildkit to master@ae9d0f5

Signed-off-by: Justin Chadwell <me@jedevc.com>

vendor/golang.org/x/oauth2/google/error.go

@@ -0,0 +1,64 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package google
+
+import (
+	"errors"
+
+	"golang.org/x/oauth2"
+)
+
+// AuthenticationError indicates there was an error in the authentication flow.
+//
+// Use (*AuthenticationError).Temporary to check if the error can be retried.
+type AuthenticationError struct {
+	err *oauth2.RetrieveError
+}
+
+func newAuthenticationError(err error) error {
+	re := &oauth2.RetrieveError{}
+	if !errors.As(err, &re) {
+		return err
+	}
+	return &AuthenticationError{
+		err: re,
+	}
+}
+
+// Temporary indicates that the network error has one of the following status codes and may be retried: 500, 503, 408, or 429.
+func (e *AuthenticationError) Temporary() bool {
+	if e.err.Response == nil {
+		return false
+	}
+	sc := e.err.Response.StatusCode
+	return sc == 500 || sc == 503 || sc == 408 || sc == 429
+}
+
+func (e *AuthenticationError) Error() string {
+	return e.err.Error()
+}
+
+func (e *AuthenticationError) Unwrap() error {
+	return e.err
+}
+
+type errWrappingTokenSource struct {
+	src oauth2.TokenSource
+}
+
+func newErrWrappingTokenSource(ts oauth2.TokenSource) oauth2.TokenSource {
+	return &errWrappingTokenSource{src: ts}
+}
+
+// Token returns the current token if it's still valid, else will
+// refresh the current token (using r.Context for HTTP client
+// information) and return the new one.
+func (s *errWrappingTokenSource) Token() (*oauth2.Token, error) {
+	t, err := s.src.Token()
+	if err != nil {
+		return nil, newAuthenticationError(err)
+	}
+	return t, nil
+}