Flip linux_arm bot to GN.

tools/mb/mb_config.pyl

 # 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.
 
 {
   # This is a map of buildbot master names -> buildbot builder names ->
   # config names (where each config name is a key in the 'configs' dict,
   # below). MB uses this dict to look up which config to use for a given bot.
   'masters': {
     # Take care when changing any of these builders to ensure that you do not
@@ skipping 692 matching lines @@
       'ChromiumOS Codesearch Builder': 'codesearch_gn',
       'cast_shell_linux': 'cast_gn_release_trybot',
       'chromeos_amd64-generic_variable': 'findit',
       'chromeos_amd64-generic_chromium_compile_only_ng': 'cros_chrome_sdk_gn',
       'chromeos_daisy_chromium_compile_only_ng': 'cros_chrome_sdk_gn',
       'chromeos_daisy_variable': 'findit',
       'chromeos_x86-generic_chromium_compile_only_ng': 'cros_chrome_sdk_gn',
       'chromeos_x86-generic_variable': 'findit',
       'chromium_presubmit': 'none',
       'closure_compilation': 'closure_compilation',
-      'linux_arm': 'swarming_gyp_release_trybot_arm',
+      'linux_arm': 'swarming_gn_release_trybot_arm',
       'linux_chromium_archive_rel_ng': 'noswarming_gn_release_bot',
       'linux_chromium_asan_rel_ng': 'swarming_asan_lsan_gyp_release_trybot',
       'linux_chromium_asan_variable': 'findit',
       'linux_chromium_browser_side_navigation_rel': 'gn_release_trybot',
       'linux_chromium_cast_variable': 'findit',
       'linux_chromium_cfi_rel_ng': 'gn_cfi_release_static_dcheck_always_on',
       'linux_chromium_chromeos_asan_rel_ng':
         'swarming_asan_lsan_chromeos_gyp_release_trybot',
       'linux_chromium_chromeos_asan_variable': 'findit',
       'linux_chromium_chromeos_compile_dbg_ng':
@@ skipping 1079 matching lines @@
     ],
 
     'swarming_gyp_debug_trybot': [
       'swarming', 'gyp', 'debug_trybot',
     ],
 
     'swarming_gyp_msan_release_bot': [
       'swarming', 'gyp', 'msan', 'release_bot',
     ],
 
-    'swarming_gyp_release_trybot_arm': [
-      'swarming', 'gyp', 'release_trybot', 'arm', 'crosscompile',
+    'swarming_gn_release_trybot_arm': [
+      'swarming', 'gn', 'release_trybot', 'arm', 'crosscompile',
     ],
 
     'swarming_gyp_syzyasan_release_trybot_x86': [
       'swarming', 'gyp', 'syzyasan', 'release_trybot', 'x86',
     ],
 
     'swarming_gyp_tsan_disable_nacl_release_bot': [
       'swarming', 'gyp', 'tsan', 'disable_nacl', 'release_bot',
     ],
 
@@ skipping 455 matching lines @@
     },
 
     'drfuzz': { 'gn_args': 'use_drfuzz=true' },
 
     'drmemory': {
       'gn_args': 'is_component_build=true enable_iterator_debugging=false',
       'gyp_defines': 'component=shared_library build_for_tool=drmemory',
     },
   },
 }