Fix GCS

Signed-off-by: Olivier Gambier <olivier@docker.com>

vendor/google.golang.org/api/googleapi/internal/uritemplates/utils.go

@@ -1,13 +1,13 @@
+// Copyright 2016 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 uritemplates
 
-func Expand(path string, expansions map[string]string) (string, error) {
-	template, err := Parse(path)
+func Expand(path string, values map[string]string) (string, error) {
+	template, err := parse(path)
 	if err != nil {
 		return "", err
 	}
-	values := make(map[string]interface{})
-	for k, v := range expansions {
-		values[k] = v
-	}
-	return template.Expand(values)
+	return template.Expand(values), nil
 }