Replace FileResource::set_labels with mutable_labels

Review URL: https://chromiumcodereview.appspot.com/23627008

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@221754 0039d316-1c4b-4281-b951-d872f2087c98

chrome/browser/google_apis/drive_api_parser.h

@@ -567,8 +567,8 @@ class FileResource {
   void set_mime_type(const std::string& mime_type) {
     mime_type_ = mime_type;
   }
-  void set_labels(const FileLabels& labels) {
-    labels_ = labels;
+  FileLabels* mutable_labels() {
+    return &labels_;
   }
   void set_created_date(const base::Time& created_date) {
     created_date_ = created_date;