Fix dependencies

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

@@ -1,33 +0,0 @@
-// Copyright 2014 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 internal
-
-import (
-	"context"
-	"net/http"
-)
-
-// HTTPClient is the context key to use with golang.org/x/net/context's
-// WithValue function to associate an *http.Client value with a context.
-var HTTPClient ContextKey
-
-// ContextKey is just an empty struct. It exists so HTTPClient can be
-// an immutable public variable with a unique type. It's immutable
-// because nobody else can create a ContextKey, being unexported.
-type ContextKey struct{}
-
-var appengineClientHook func(context.Context) *http.Client
-
-func ContextClient(ctx context.Context) *http.Client {
-	if ctx != nil {
-		if hc, ok := ctx.Value(HTTPClient).(*http.Client); ok {
-			return hc
-		}
-	}
-	if appengineClientHook != nil {
-		return appengineClientHook(ctx)
-	}
-	return http.DefaultClient
-}