remoting: Suppress a clang warning that fires in atl headers.

remoting/remoting_host_win.gypi

 # Copyright 2014 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': {
     'remoting_host_installer_win_roots': [
       'host/installer/win/',
     ],
     'remoting_host_installer_win_files': [
@@ skipping 232 matching lines @@
               'AdditionalOptions': [
                 # Export the proxy/stub entry points. Note that the generated
                 # routines have 'Ps' prefix to avoid conflicts with our own
                 # DllMain().
                 '/EXPORT:DllGetClassObject=PsDllGetClassObject,PRIVATE',
                 '/EXPORT:DllCanUnloadNow=PsDllCanUnloadNow,PRIVATE',
                 '/EXPORT:DllRegisterServer=PsDllRegisterServer,PRIVATE',
                 '/EXPORT:DllUnregisterServer=PsDllUnregisterServer,PRIVATE',
               ],
             },
+            'conditions': [
+              ['clang==1', {
+                # atlbase.h contains a global "using namespace WTL;".
+                # TODO: Remove once remoting/host/verify_config_window_win.h no
+                # longer depends on atlbase.h, http://crbug.com/5027
+                'VCCLCompilerTool': {
+                  'AdditionalOptions': ['-Wno-header-hygiene'],
+                },
+              }],
+            ],
           },
         },  # end of target 'remoting_core'
         {
           'target_name': 'remoting_desktop',
           'type': 'executable',
           'variables': { 'enable_wexit_time_destructors': 1, },
           'defines': [
             'BINARY=BINARY_DESKTOP',
           ],
           'dependencies': [
@@ skipping 339 matching lines @@
                 '--defs', '<@(_defs)',
               ],
             },
           ],  # actions
         }, # end of target 'remoting_me2me_host_archive'
       ],  # end of 'targets'
     }],  # '<(wix_path) != ""'
 
   ],  # end of 'conditions'
 }