gn: Make target_cpu=x86 v8_target_arch=arm builds generate build files.

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 2097 matching lines @@
       'gyp_defines': 'use_goma=1',
     },
 
     'gpu_tests': {
       'mixins': ['archive_gpu_tests', 'chrome_with_codecs'],
     },
 
     'gyp': {'type': 'gyp'},
 
     'hybrid': {
-      'gn_args': 'v8_target_cpu="arm" target_cpu="x86"',
+      'gn_args': 'v8_target_arch="arm" target_cpu="x86"',
       'gyp_defines': 'v8_target_arch=arm target_arch=ia32 host_arch=x86_64',
       'mixins': ['disable_nacl'],
     },
 
     'internal_gles2_conform_tests': {
       'gn_args': 'internal_gles2_conform_tests=true',
       'gyp_defines': 'internal_gles2_conform_tests=1',
     },
 
     'java_coverage': {
@@ skipping 198 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',
     },
   },
 }