Fix SCons modules build on Windows:...

base/base_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.
 
 __doc__ = """
 Configuration for building base_unittests{,.exe}.
 """
 
 Import('env')
 
@@ skipping 164 matching lines @@
   ])
 
 if env['PLATFORM'] == 'darwin':
   # Mac-specific tests.
   input_files.extend([
       'platform_test_mac.mm',
   ])
 
 base_unittests = env.ChromeTestProgram('base_unittests', input_files)
 
-env.Depends(base_unittests, '$EXPORTED_SYMBOLS_FILE')
+if env['PLATFORM'] == 'posix':
+  env.Depends(base_unittests, '$EXPORTED_SYMBOLS_FILE')
 
 # Install up a level to allow unit test path assumptions to be valid.
 installed_base_unittests = env.Install('$TARGET_ROOT', base_unittests)
 
 env.Alias('base', installed_base_unittests)
 
 # TODO(sgk) should this be moved into base.lib like everything else?  This will
 # require updating a bunch of other SConscripts which link directly against
 # this generated object file.
 env.StaticObject('perftimer.cc')
 
 # Since run_all_perftests supplies a main, we cannot have it in base.lib
 env.StaticObject('run_all_perftests.cc')