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

chrome/test/ui/ui_tests.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.SConscript([
     '$BASE_DIR/using_base.scons',
@@ skipping 27 matching lines @@
         'browser',
         'browser_views',
         'common',
         'npapi_layout_test_plugin',
         'npapi_test_plugin',
         'port',
         'security_tests',
     ],
 )
 
-if env['PLATFORM'] == 'win32':
+if env.Bit('windows'):
   env.Prepend(
       CPPPATH = [
           '$CHROME_DIR/tools/build/win',
       ],
       LINKFLAGS = [
           '/INCREMENTAL',
 
           '/safeseh',
           '/dynamicbase',
           '/ignore:4199',
@@ skipping 57 matching lines @@
     '$CHROME_DIR/test/accessibility/browser_impl.cc',
     '$CHROME_DIR/test/accessibility/keyboard_util.cc',
     '$CHROME_DIR/test/accessibility/registry_util.cc',
     '$CHROME_DIR/test/accessibility/tab_impl.cc',
     '$CHROME_DIR/test/automation/automation_proxy_uitest.cc',
     '$CHROME_DIR/test/perf/mem_usage.cc',
     '$CHROME_DIR/test/reliability/page_load_test$OBJSUFFIX',
     '$NET_DIR/url_request/url_request_test_job$OBJSUFFIX',
 ]
 
-if env['PLATFORM'] == 'win32':
+if env.Bit('windows'):
   ui_test_files.extend([
       '$CHROME_DIR/browser/views/find_bar_win_interactive_uitest.cc',
       '$CHROME_DIR/browser/views/find_bar_win_uitest.cc',
   ])
 
 env.ChromeTestProgram('ui_tests',  ui_test_files)