Updating android_webview bisect bot to include arch name.

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 821 matching lines @@
       'android_nexus5_perf_bisect': 'gn_official_goma_minimal_symbols_android',
       'android_nexus6_perf_bisect': 'gn_official_goma_minimal_symbols_android',
       'android_nexus7_perf_bisect': 'gn_official_goma_minimal_symbols_android',
       'android_nexus9_perf_bisect':
         'gn_official_goma_minimal_symbols_android_arm64',
       'android_one_perf_bisect': 'gn_official_goma_minimal_symbols_android',
       'android_perf_bisect_builder':
         'gn_official_goma_minimal_symbols_android',
       'android_s5_perf_bisect': 'gn_official_goma_minimal_symbols_android',
       'android_s5_perf_cq': 'gn_official_goma_minimal_symbols_android',
-      'android_webview_aosp_perf_bisect':
+      'android_webview_arm64_aosp_perf_bisect':
         'gn_official_goma_minimal_symbols_android',
       'linux_fyi_perf_bisect': 'gn_official_goma',
       'linux_perf_bisect': 'gn_official_goma',
       'linux_perf_bisect_builder': 'gn_official_goma',
       'linux_perf_cq': 'gn_official_goma',
       'mac_10_10_perf_bisect': 'gyp_official_goma',
       'mac_10_11_perf_bisect': 'gyp_official_goma',
       'mac_fyi_perf_bisect': 'gyp_official_goma',
       'mac_hdd_perf_bisect': 'gyp_official_goma',
       'mac_perf_bisect_builder': 'gyp_official_goma',
@@ skipping 1446 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',
     },
   },
 }