Add mac_util, including MacOSXMinorVersion(), MacOSXVersion(), and MacModelAndBoard()

util/util.gyp

 # Copyright 2014 The Crashpad Authors. All rights reserved.
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
 # You may obtain a copy of the License at
 #
 #     http://www.apache.org/licenses/LICENSE-2.0
 #
 # Unless required by applicable law or agreed to in writing, software
 # distributed under the License is distributed on an "AS IS" BASIS,
@@ skipping 16 matching lines @@
       ],
       'sources': [
         'file/fd_io.cc',
         'file/fd_io.h',
         'file/file_writer.cc',
         'file/file_writer.h',
         'file/string_file_writer.cc',
         'file/string_file_writer.h',
         'mac/launchd.h',
         'mac/launchd.mm',
+        'mac/mac_util.cc',
+        'mac/mac_util.h',
         'mach/task_memory.cc',
         'mach/task_memory.h',
         'misc/initialization_state.h',
         'misc/initialization_state_dcheck.cc',
         'misc/initialization_state_dcheck.h',
         'misc/uuid.cc',
         'misc/uuid.h',
         'posix/process_util.h',
         'posix/process_util_mac.cc',
         'stdlib/cxx.h',
@@ skipping 30 matching lines @@
         '../third_party/gtest/gtest.gyp:gtest',
         '../third_party/gtest/gtest.gyp:gtest_main',
         '../third_party/mini_chromium/mini_chromium/base/base.gyp:base',
       ],
       'include_dirs': [
         '..',
       ],
       'sources': [
         'file/string_file_writer_test.cc',
         'mac/launchd_test.mm',
+        'mac/mac_util_test.mm',
         'mach/task_memory_test.cc',
         'misc/initialization_state_dcheck_test.cc',
         'misc/initialization_state_test.cc',
         'misc/uuid_test.cc',
         'posix/process_util_test.cc',
         'stdlib/strlcpy_test.cc',
       ],
     },
   ],
 }