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

chrome/renderer/renderer.scons

Index: chrome/renderer/renderer.scons
===================================================================
--- chrome/renderer/renderer.scons	(revision 7247)
+++ chrome/renderer/renderer.scons	(working copy)
@@ -20,7 +20,7 @@
     ],
 )
 
-if env['PLATFORM'] == 'win32':
+if env.Bit('windows'):
   env.Prepend(
       CPPPATH = [
           '$CHROME_DIR/tools/build/win',
@@ -53,7 +53,7 @@
 ]
 
 # 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',
@@ -72,7 +72,7 @@
     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',
@@ -100,5 +100,5 @@
 
 
 # TODO(port): Enable for Mac.
-if env['PLATFORM'] in ('posix', 'win32'):
+if not env.Bit('mac'):
   env.ChromeStaticLibrary('renderer', input_files)