move enable_localaccount.sh, make pam_offline use it

src/platform/pam_offline/SConstruct

 # -*- python -*-
 
 # Copyright (c) 2009-2010 The Chromium OS 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 os
 
 env = Environment()
 
@@ skipping 23 matching lines @@
   value = os.environ.get(key)
   if value != None:
     env[key] = Split(value)
 env['CCFLAGS'] += ['-fPIC', '-fno-exceptions', '-Wall']
 
 # Fix issue with scons not passing pkg-config vars through the environment.
 for key in Split('PKG_CONFIG_LIBDIR PKG_CONFIG_PATH'):
   if os.environ.has_key(key):
     env['ENV'][key] = os.environ[key]
 
+# Enable local account only if user has specified one
+if os.path.exists('pam_localaccount.h'):
+  print """
+WARNING: pam local account is enabled!  If you don't want this, remove
+pam_localaccount.h.
+"""
+  env.Append(CPPDEFINES=['CHROMEOS_PAM_LOCALACCOUNT'])
+
 env_lib = env.Clone()
 env_lib.SharedLibrary('chromeos_pam_offline', pam_sources)
 
 env_test = env.Clone()
 env_test.Append(LIBS=['gflags', 'gtest', 'pcrecpp', 'curl'])
 env_test.Program('pam_offline_unittests', pam_sources + test_sources)