Inline GPU and opus GYP files into GN build.

gpu/gles2_cmd_helper.gypi

Index: gpu/gles2_cmd_helper.gypi
diff --git a/gpu/gles2_cmd_helper.gypi b/gpu/gles2_cmd_helper.gypi
deleted file mode 100644
index 523a7614bbb6a4fa41d165211891c71e691637e2..0000000000000000000000000000000000000000
--- a/gpu/gles2_cmd_helper.gypi
+++ /dev/null
@@ -1,12 +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.
-
-{
-  # Library helps make GLES2 command buffers.
-  'sources': [
-    'command_buffer/client/gles2_cmd_helper.cc',
-    'command_buffer/client/gles2_cmd_helper.h',
-    'command_buffer/client/gles2_cmd_helper_autogen.h',
-  ],
-}