Remove GYP files.

third_party/mt19937ar/mt19937ar.gyp

Index: third_party/mt19937ar/mt19937ar.gyp
diff --git a/third_party/mt19937ar/mt19937ar.gyp b/third_party/mt19937ar/mt19937ar.gyp
deleted file mode 100644
index 6ea8d31f9b2fdd187ce71e507c1d53307c44cda2..0000000000000000000000000000000000000000
--- a/third_party/mt19937ar/mt19937ar.gyp
+++ /dev/null
@@ -1,19 +0,0 @@
-# Copyright (c) 2012 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.
-
-{
-  'targets': [
-    {
-      'target_name': 'mt19937ar',
-      'type': 'static_library',
-      'sources': [
-        'mt19937ar.cc',
-        'mt19937ar.h',
-      ],
-      'include_dirs': [
-        '../..',
-      ],
-    },
-  ],
-}