Move GLIB_DISABLE_DEPRECATION_WARNINGS define to a more general place.

build/linux/system.gyp

 # 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': {
     'conditions': [
       ['sysroot!=""', {
         'pkg-config': '<(chroot_cmd) ./pkg-config-wrapper "<(sysroot)" "<(target_arch)" "<(system_libdir)"',
       }, {
@@ skipping 549 matching lines @@
       ],
     },
     {
       'target_name': 'gio',
       'type': 'static_library',
       'conditions': [
         ['use_gio==1 and _toolset=="target"', {
           'cflags': [
             '<!@(<(pkg-config) --cflags gio-2.0)',
           ],
+          'variables': {
+            'gio_warning_define': [
+              # glib >=2.40 deprecate g_settings_list_schemas in favor of
+              # g_settings_schema_source_list_schemas. This function is not
+              # available on earlier versions that we still need to support
+              # (specifically, 2.32), so disable the warning.
+              # TODO(mgiuca): Remove this suppression (and variable) when we
+              # drop support for Ubuntu 13.10 (saucy) and earlier. Update the
+              # code to use g_settings_schema_source_list_schemas instead.
+              'GLIB_DISABLE_DEPRECATION_WARNINGS',
+            ],
+          },
+          'defines': [
+            '<(gio_warning_define)',
+          ],
           'direct_dependent_settings': {
             'cflags': [
               '<!@(<(pkg-config) --cflags gio-2.0)',
             ],
             'defines': [
               'USE_GIO',
+              '<(gio_warning_define)',
             ],
             'include_dirs': [
               '<(SHARED_INTERMEDIATE_DIR)',
             ],
           },
           'include_dirs': [
             '../..',
           ],
           'link_settings': {
             'ldflags': [
@@ skipping 466 matching lines @@
                   '-Wno-header-guard',
                 ],
               },
             }],
           ]
         }],
       ],
     },
   ],
 }