Add a wrapper for grit_action.gypi for chrome specific variables.

chrome/chrome_features.gypi

Index: chrome/chrome_features.gypi
diff --git a/chrome/chrome_features.gypi b/chrome/chrome_features.gypi
index 1042f413cf4882f7fdf02b029b5f3aaefc8847bc..b78a4dae686a42f64d5ed8838961e69616ae5780 100644
--- a/chrome/chrome_features.gypi
+++ b/chrome/chrome_features.gypi
@@ -1,7 +1,7 @@
 # Copyright 2015 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.
- 
+
 # This is the GYP equivalent of //chrome/common/features.gni.
 # Please keep in sync!
 
@@ -38,6 +38,6 @@
     'chrome_grit_defines': [
       '-D', 'enable_google_now=<(enable_google_now)',
       '-D', 'use_vulcanize=<(use_vulcanize)',
-    ]
+    ],
   },
 }