Convert from using env['PLATFORM'] directly to using the more flexible...

chrome/installer/mini_installer/installer_unittests.scons

 # Copyright (c) 2006-2008 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.
 
 Import('env')
 
 env = env.Clone()
 
 env.ApplySConscript([
     '$BASE_DIR/using_base.scons',
     '$GTEST_DIR/../using_gtest.scons',
     '$ICU38_DIR/using_icu38.scons',
 ])
 
 env.Prepend(
     CPPPATH = [
         '$CHROME_SRC_DIR',
     ],
     LIBS = [
         'common',
         'util',
     ],
 )
 
-if env['PLATFORM'] == 'win32':
+if env.Bit('windows'):
   env.FilterOut(
       LIBS = ['DelayImp.lib'],
   )
 
   env.Prepend(
       LINKFLAGS = [
           '/INCREMENTAL',
           '/DEBUG',
 
           '/DELAYLOAD:"dwmapi.dll"',
@@ skipping 23 matching lines @@
     '../util/delete_reg_value_work_item_unittest.cc',
     '../util/delete_tree_work_item_unittest.cc',
     '../util/google_chrome_distribution_unittest.cc',
     '../util/helper_unittest.cc',
     '../util/run_all_unittests.cc',
     '../util/set_reg_value_work_item_unittest.cc',
     '../util/work_item_list_unittest.cc',
 ]
 
 env.ChromeTestProgram('installer_unittests', input_files)