Move sync_internals resources and constants to //components.

chrome/browser/resources/sync_internals/sync_index.js

Index: chrome/browser/resources/sync_internals/sync_index.js
diff --git a/chrome/browser/resources/sync_internals/sync_index.js b/chrome/browser/resources/sync_internals/sync_index.js
deleted file mode 100644
index 7cce623df43f1377c4a570c4278ab508bc8777ee..0000000000000000000000000000000000000000
--- a/chrome/browser/resources/sync_internals/sync_index.js
+++ /dev/null
@@ -1,12 +0,0 @@
-// Copyright (c) 2011 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-// Allow platform specific CSS rules.
-//
-// TODO(akalin): BMM and options page does something similar, too.
-// Move this to util.js.
-if (cr.isWindows)
-  document.documentElement.setAttribute('os', 'win');
-
-cr.ui.decorate('tabbox', cr.ui.TabBox);