Touch BUILD.gn to trigger a dependency

BUILD.gn

 # Copyright 2014 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 config is applied to targets that depend on libvpx.
-config("libvpx_external_config") {
-  include_dirs = [
-    "//third_party/libvpx_new/source/libvpx",
-  ]
-}
-
 static_library("libvpx") {
   deps = [
     "//third_party/libvpx_new",
   ]
-  public_configs = [ ":libvpx_external_config" ]
+  include_dirs = [
+    "//third_party/libvpx_new/source/libvpx",
+  ]
 }