Update from https://crrev.com/320343

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 10 matching lines @@
         'egl/surface.h',
       ],
       'defines': [
         'EGLAPI=',
         'EGLAPIENTRY=',
       ],
       # TODO(jschuh): crbug.com/167187 fix size_t to int truncations.
       'msvs_disabled_warnings': [ 4267, ],
     },
     {
+      # GN version: //gpu/gles2_conform_support/native
       'target_name': 'egl_main_native',
       'type': 'static_library',
       'dependencies': [
         'egl_native',
         '../../third_party/khronos/khronos.gyp:khronos_headers',
       ],
       'sources': [
         '<@(bootstrap_sources_native)',
       ],
       'defines': [
         'GLES2_CONFORM_SUPPORT_ONLY',
         'GTF_GLES20',
         'EGLAPI=',
         'EGLAPIENTRY=',
       ],
     },
     {
+      # GN version: //gpu/gles2_conform_support/native:windowless
       'target_name': 'egl_main_windowless',
       'type': 'static_library',
       'dependencies': [
         'egl_native',
         '../../third_party/khronos/khronos.gyp:khronos_headers',
       ],
       'sources': [
         'native/egl_native.cc',
         'native/egl_native_windowless.cc',
         'native/main.cc',
@@ skipping 29 matching lines @@
         'EGLAPI=',
         'EGLAPIENTRY=',
       ],
       'sources': [
         '<@(bootstrap_sources_native)',
         'gles2_conform_support.c'
       ],
     },
   ],
 }