vendor: update all dependencies

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

@@ -26,17 +26,13 @@ import (
 // Deprecated: Use context.Background() or context.TODO() instead.
 var NoContext = context.TODO()
 
-// RegisterBrokenAuthHeaderProvider registers an OAuth2 server
-// identified by the tokenURL prefix as an OAuth2 implementation
-// which doesn't support the HTTP Basic authentication
-// scheme to authenticate with the authorization server.
-// Once a server is registered, credentials (client_id and client_secret)
-// will be passed as parameters in the request body rather than being present
-// in the Authorization header.
-// See https://code.google.com/p/goauth2/issues/detail?id=31 for background.
-func RegisterBrokenAuthHeaderProvider(tokenURL string) {
-	internal.RegisterBrokenAuthHeaderProvider(tokenURL)
-}
+// RegisterBrokenAuthHeaderProvider previously did something. It is now a no-op.
+//
+// Deprecated: this function no longer does anything. Caller code that
+// wants to avoid potential extra HTTP requests made during
+// auto-probing of the provider's auth style should set
+// Endpoint.AuthStyle.
+func RegisterBrokenAuthHeaderProvider(tokenURL string) {}
 
 // Config describes a typical 3-legged OAuth2 flow, with both the
 // client application information and the server's endpoint URLs.
@@ -71,13 +67,38 @@ type TokenSource interface {
 	Token() (*Token, error)
 }
 
-// Endpoint contains the OAuth 2.0 provider's authorization and token
+// Endpoint represents an OAuth 2.0 provider's authorization and token
 // endpoint URLs.
 type Endpoint struct {
 	AuthURL  string
 	TokenURL string
+
+	// AuthStyle optionally specifies how the endpoint wants the
+	// client ID & client secret sent. The zero value means to
+	// auto-detect.
+	AuthStyle AuthStyle
 }
 
+// AuthStyle represents how requests for tokens are authenticated
+// to the server.
+type AuthStyle int
+
+const (
+	// AuthStyleAutoDetect means to auto-detect which authentication
+	// style the provider wants by trying both ways and caching
+	// the successful way for the future.
+	AuthStyleAutoDetect AuthStyle = 0
+
+	// AuthStyleInParams sends the "client_id" and "client_secret"
+	// in the POST body as application/x-www-form-urlencoded parameters.
+	AuthStyleInParams AuthStyle = 1
+
+	// AuthStyleInHeader sends the client_id and client_password
+	// using HTTP Basic Authorization. This is an optional style
+	// described in the OAuth2 RFC 6749 section 2.3.1.
+	AuthStyleInHeader AuthStyle = 2
+)
+
 var (
 	// AccessTypeOnline and AccessTypeOffline are options passed
 	// to the Options.AuthCodeURL method. They modify the
@@ -124,7 +145,7 @@ func SetAuthURLParam(key, value string) AuthCodeOption {
 //
 // Opts may include AccessTypeOnline or AccessTypeOffline, as well
 // as ApprovalForce.
-// It can also be used to pass the PKCE challange.
+// It can also be used to pass the PKCE challenge.
 // See https://www.oauth.com/oauth2-servers/pkce/ for more info.
 func (c *Config) AuthCodeURL(state string, opts ...AuthCodeOption) string {
 	var buf bytes.Buffer