Undo the startup_helper_win.h change in r143501 because that breaks the sandbox in component builds.

content/content_shell.gypi

 # Copyright (c) 2012 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.
 
 {
   'variables': {
     'content_shell_product_name': 'Content Shell',
   },
   'targets': [
     {
@@ skipping 232 matching lines @@
         'chromium_code': 1,
       },
       'dependencies': [
         'content_shell_lib',
         'content_shell_pak',
       ],
       'include_dirs': [
         '..',
       ],
       'sources': [
+        'app/startup_helper_win.cc',
         'shell/shell_main.cc',
       ],
       'mac_bundle_resources': [
         'shell/mac/app.icns',
         'shell/mac/app-Info.plist',
       ],
       # TODO(mark): Come up with a fancier way to do this.  It should only
       # be necessary to list app-Info.plist once, not the three times it is
       # listed here.
       'mac_bundle_resources!': [
@@ skipping 309 matching lines @@
                 '-buildfile',
                 '<(DEPTH)/content/shell/android/content_shell_apk.xml',
               ]
             }
           ],
         },
       ],
     }],  # OS=="android"
   ]
 }