Address some TODO(GYP)s in the GN build.

build/gn_migration.gypi

 # Copyright (c) 2015 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 file defines five targets that we are using to track the progress of the
 # GYP->GN migration:
 #
 # 'both_gn_and_gyp' lists what GN is currently capable of building and should
 # match the 'both_gn_and_gyp' target in //BUILD.gn.
 #
 # 'gyp_all' Should include everything built when building "all"; i.e., if you
 # type 'ninja gyp_all' and then 'ninja all', the second build should do
 # nothing. 'gyp_all' should just depend on the other four targets.
 #
 # 'gyp_remaining' lists all of the targets that still need to be converted,
 # i.e., all of the other (non-empty) targets that a GYP build will build.
-#
-# TODO(GYP): crbug.com/481694. Add a build step to the bot that enforces the
-# above contracts.
 
 {
   'includes': [
     '../media/media_variables.gypi'
   ],
   'targets': [
     {
       'target_name': 'gyp_all',
       'type': 'none',
       'dependencies': [
@@ skipping 744 matching lines @@
         }],
         ['OS=="android" and target_arch != "x64"', {
           'dependencies': [
             '../third_party/android_platform/relocation_packer.gyp:android_relocation_packer_unittests#host'
           ],
         }],
       ],
     },
   ]
 }