ios: Default GYP_GENERATORS to ninja, and error out if GYP_GENERATORS is xcode

build/gyp_chromium.py

 # 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.
 
 """This script is wrapper for Chromium that adds some support for how GYP
 is invoked by Chromium beyond what can be done in the gclient hooks.
 """
 
 import argparse
 import gc
@@ skipping 266 matching lines @@
     print 'Error: make gyp generator not supported (check GYP_GENERATORS).'
     sys.exit(1)
 
   # We explicitly don't support the native msvs gyp generator. Be nice and
   # fail here, rather than generating broken projects.
   if re.search(r'(^|,|\s)msvs($|,|\s)', os.environ.get('GYP_GENERATORS', '')):
     print 'Error: msvs gyp generator not supported (check GYP_GENERATORS).'
     print 'Did you mean to use the `msvs-ninja` generator?'
     sys.exit(1)
 
+  # We explicitly don't support the native xcode gyp generator. Be nice and
+  # fail here, rather than generating broken projects.
+  if re.search(r'(^|,|\s)xcode($|,|\s)', os.environ.get('GYP_GENERATORS', '')):
+    print 'Error: xcode gyp generator not supported (check GYP_GENERATORS).'
+    print 'Did you mean to use the `xcode-ninja` generator?'
+    sys.exit(1)
+
   # If CHROMIUM_GYP_SYNTAX_CHECK is set to 1, it will invoke gyp with --check
   # to enfore syntax checking.
   syntax_check = os.environ.get('CHROMIUM_GYP_SYNTAX_CHECK')
   if syntax_check and int(syntax_check):
     args.append('--check')
 
   # TODO(dmikurube): Remove these checks and messages after a while.
   if ('linux_use_tcmalloc' in gyp_vars_dict or
       'android_use_tcmalloc' in gyp_vars_dict):
     print '*****************************************************************'
@@ skipping 53 matching lines @@
     if vs2013_runtime_dll_dirs:
       x64_runtime, x86_runtime = vs2013_runtime_dll_dirs
       vs_toolchain.CopyVsRuntimeDlls(
         os.path.join(chrome_src, GetOutputDirectory()),
         (x86_runtime, x64_runtime))
 
   sys.exit(gyp_rc)
 
 if __name__ == '__main__':
   sys.exit(main())