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

chrome/test/chrome_plugin/test_chrome_plugin.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([
     '$BASE_DIR/using_base.scons',
     '$CHROME_SRC_DIR/build/using_googleurl.scons',
     '$ICU38_DIR/using_icu38.scons',
 ])
 
 env.Prepend(
     CPPPATH = [
         '$CHROME_SRC_DIR',
     ],
 )
 
-if env['PLATFORM'] == 'win32':
+if env.Bit('windows'):
   env.Prepend(
       LINKFLAGS = [
           '/INCREMENTAL',
 
           '/MANIFEST',
           '/DELAYLOAD:"dwmapi.dll"',
           '/DELAYLOAD:"uxtheme.dll"',
           '/MACHINE:X86',
           '/FIXED:No',
 
           '/safeseh',
           '/dynamicbase',
           '/ignore:4199',
           '/nxcompat',
 
           '/DEBUG',
       ],
       LIBS = [
           'winmm.lib',
       ],
   )
 
 input_files = [
     'test_chrome_plugin.cc',
 ]
 
-if env['PLATFORM'] == 'win32':
+if env.Bit('windows'):
   input_files.extend([
       'test_chrome_plugin.def',
   ])
 
 env.ChromeSharedLibrary('test_chrome_plugin', input_files)