Remove 'ChromiumOS GN' builders from master.chromium.chromiumos.

scripts/slave/recipe_modules/chromium_tests/trybots.py

 # Copyright 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.
 
 from recipe_engine.types import freeze
 
 
 def simple_bot(bot_id, analyze_mode=None):
   return {
     'bot_ids': [bot_id],
@@ skipping 240 matching lines @@
       'linux_chromium_dbg_32_ng': simple_bot({
         'mastername': 'chromium.linux',
         'buildername': 'Linux Builder (dbg)(32)',
         'tester': 'Linux Tests (dbg)(1)(32)',
       }),
       'linux_chromium_dbg_ng': simple_bot({
         'mastername': 'chromium.linux',
         'buildername': 'Linux Builder (dbg)',
         'tester': 'Linux Tests (dbg)(1)',
       }),
-      'linux_chromium_gn_chromeos_dbg': simple_bot({
-        'mastername': 'chromium.chromiumos',
-        'buildername': 'Linux ChromiumOS GN (dbg)',
-      }),
-      'linux_chromium_gn_chromeos_rel': simple_bot({
-        'mastername': 'chromium.chromiumos',
-        'buildername': 'Linux ChromiumOS GN',
-      }),
       'linux_chromium_rel_ng': {
         'bot_ids': [
           {
             'mastername': 'chromium.linux',
             'buildername': 'Linux Builder',
             'tester': 'Linux Tests',
           },
           {
             'mastername': 'chromium.gpu',
             'buildername': 'GPU Linux Builder',
@@ skipping 293 matching lines @@
         'mastername': 'client.v8.fyi',
         'buildername': 'V8 Linux GN',
       }),
       'v8_android_chromium_gn_dbg': simple_bot({
         'mastername': 'client.v8.fyi',
         'buildername': 'V8 Android GN (dbg)',
       }),
     },
   },
 })