gpu: Convert egl_native target to GN build.

gpu/gles2_conform_support/gles2_conform_support.gyp

 # 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.
 
 {
   'variables': {
     'chromium_code': 1,
     # These are defined here because we want to be able to compile them on
     # the buildbots without needed the OpenGL ES 2.0 conformance tests
     # which are not open source.
@@ skipping 12 matching lines @@
        'bootstrap_sources_native': [
          'native/egl_native.cc',
          'native/egl_native_win.cc',
        ],
      }],
    ],
 
   },
   'targets': [
     {
+      # GN version: //gpu/gles2_conform_support/egl
       'target_name': 'egl_native',
       'type': 'static_library',
       'dependencies': [
         '../../base/base.gyp:base',
         '../../gpu/gpu.gyp:command_buffer_service',
         '../../gpu/gpu.gyp:gles2_implementation_no_check',
         '../../gpu/gpu.gyp:gpu',
         '../../third_party/khronos/khronos.gyp:khronos_headers',
         '../../ui/base/ui_base.gyp:ui_base',
         '../../ui/gfx/gfx.gyp:gfx',
@@ skipping 76 matching lines @@
         'EGLAPI=',
         'EGLAPIENTRY=',
       ],
       'sources': [
         '<@(bootstrap_sources_native)',
         'gles2_conform_support.c'
       ],
     },
   ],
 }