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

chrome/renderer/renderer.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([
     '$CHROME_DIR/third_party/wtl/using_wtl.scons',
     '$ICU38_DIR/using_icu38.scons',
     '$NPAPI_DIR/using_npapi.scons',
     '$SKIA_DIR/using_skia.scons',
 ], {'env':env})
 
 env.Prepend(
     CPPPATH = [
         '$TARGET_ROOT/grit_derived_sources',
         '$CHROME_SRC_DIR',
     ],
 )
 
-if env['PLATFORM'] == 'win32':
+if env.Bit('windows'):
   env.Prepend(
       CPPPATH = [
           '$CHROME_DIR/tools/build/win',
       ],
   )
 
 input_files = [
     'about_handler.cc',
     'chrome_plugin_host.cc',
     'debug_message_handler.cc',
@@ skipping 12 matching lines @@
     'visitedlink_slave.cc',
     'webplugin_delegate_proxy.cc',
 
     'automation/dom_automation_controller.cc',
 
     'net/render_dns_master.cc',
     'net/render_dns_queue.cc',
 ]
 
 # TODO(port): Port these to Linux
-if env['PLATFORM'] == 'posix':
+if env.Bit('linux'):
   to_be_ported_files = [
       'chrome_plugin_host.cc',
       'debug_message_handler.cc',
       'external_js_object.cc',
       'net/render_dns_master.cc',
       'plugin_channel_host.cc',
       'render_process.cc',
       'render_thread.cc',
       'render_view.cc',
       'render_widget.cc',
       'renderer_glue.cc',
       'renderer_main.cc',
       'webplugin_delegate_proxy.cc',
   ]
   for remove in to_be_ported_files:
     input_files.remove(remove)
 
 # TODO(port): Port these to Mac
-if env['PLATFORM'] == 'darwin':
+if env.Bit('mac'):
   to_be_ported_files = [
       'about_handler.cc',
       'chrome_plugin_host.cc',
       'debug_message_handler.cc',
       'dom_ui_bindings.cc',
       'external_host_bindings.cc',
       'external_js_object.cc',
       'greasemonkey_slave.cc',
       'localized_error.cc',
       'plugin_channel_host.cc',
       'render_process.cc',
       'render_thread.cc',
       'render_view.cc',
       'render_widget.cc',
       'renderer_glue.cc',
       'renderer_main.cc',
       'visitedlink_slave.cc',
       'webplugin_delegate_proxy.cc',
       'automation/dom_automation_controller.cc',
       'net/render_dns_master.cc',
       'net/render_dns_queue.cc',
   ]
   for remove in to_be_ported_files:
     input_files.remove(remove)
 
 
 # TODO(port): Enable for Mac.
-if env['PLATFORM'] in ('posix', 'win32'):
+if not env.Bit('mac'):
   env.ChromeStaticLibrary('renderer', input_files)