RefCounted types should not have public destructors, chromeos edition

chrome/browser/chromeos/gdata/gdata_file_system_unittest.cc

Index: chrome/browser/chromeos/gdata/gdata_file_system_unittest.cc
diff --git a/chrome/browser/chromeos/gdata/gdata_file_system_unittest.cc b/chrome/browser/chromeos/gdata/gdata_file_system_unittest.cc
index 41f5b5d7b754ba80905d810d087cc0c49c3ca4bc..b97fb0aea6c1736a43d8b8ecf573ca0b284d8b77 100644
--- a/chrome/browser/chromeos/gdata/gdata_file_system_unittest.cc
+++ b/chrome/browser/chromeos/gdata/gdata_file_system_unittest.cc
@@ -1214,7 +1214,6 @@ class GDataFileSystemTest : public testing::Test {
           quota_bytes_total_(0),
           quota_bytes_used_(0),
           file_proto_(NULL) {}
-    virtual ~CallbackHelper() {}
 
     virtual void GetFileCallback(base::PlatformFileError error,
                                  const FilePath& file_path,
@@ -1285,6 +1284,12 @@ class GDataFileSystemTest : public testing::Test {
     scoped_ptr<GDataEntryProto> entry_proto_;
     scoped_ptr<GDataFileProto> file_proto_;
     scoped_ptr<GDataDirectoryProto> directory_proto_;
+
+   protected:
+    virtual ~CallbackHelper() {}
+
+   private:
+    friend class base::RefCountedThreadSafe<CallbackHelper>;
   };
 
   MessageLoopForUI message_loop_;