Adds an iOS implementation of base::SystemMonitor.

base/base.gypi

 # Copyright (c) 2012 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.
 
 {
   'target_defaults': {
     'variables': {
       'base_target': 0,
     },
     'target_conditions': [
@@ skipping 330 matching lines @@
           'synchronization/spin_wait.h',
           'synchronization/waitable_event.h',
           'synchronization/waitable_event_posix.cc',
           'synchronization/waitable_event_watcher.h',
           'synchronization/waitable_event_watcher_posix.cc',
           'synchronization/waitable_event_watcher_win.cc',
           'synchronization/waitable_event_win.cc',
           'system_monitor/system_monitor.cc',
           'system_monitor/system_monitor.h',
           'system_monitor/system_monitor_android.cc',
+          'system_monitor/system_monitor_ios.mm',
           'system_monitor/system_monitor_mac.mm',
           'system_monitor/system_monitor_posix.cc',
           'system_monitor/system_monitor_win.cc',
           'sys_byteorder.h',
           'sys_info.h',
           'sys_info_android.cc',
           'sys_info_chromeos.cc',
           'sys_info_freebsd.cc',
           'sys_info_linux.cc',
           'sys_info_mac.cc',
@@ skipping 205 matching lines @@
               ['include', '^sys_string_conversions_mac\\.'],
               ['include', '^time_mac\\.'],
               ['include', '^worker_pool_mac\\.'],
               # TODO(ios): Remove these as base/ is unforked.
               # For now, exclude everything that doesn't build as-is, just to
               # get something building on a bot.
               ['exclude', '^hi_res_timer_manager'],
               ['exclude', '^json'],
               ['exclude', '^message_pump'],
               ['exclude', '^process_util'],
-              ['exclude', '^system_monitor'],
               ['exclude', '^values'],
             ],
           }],
           ['OS != "mac" or >(nacl_untrusted_build)==1', {
               'sources!': [
                 'mac/scoped_aedesc.h'
               ],
           }],
           # For now, just test the *BSD platforms enough to exclude them.
           # Subsequent changes will include them further.
@@ skipping 56 matching lines @@
           ['<(chromeos)!=1 or >(nacl_untrusted_build)==1', {
             'sources/': [
               ['exclude', '^chromeos/'],
             ],
           }],
         ],
       }],
     ],
   },
 }