Add initial support for native Linux desktop notifications

chrome/common/features.gni

 # Copyright 2015 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.
 
 import("//build/config/chrome_build.gni")
 import("//build/config/chromecast_build.gni")
 import("//build/config/compiler/compiler.gni")
 import("//build/config/features.gni")
 import("//device/vr/features.gni")
 import("//extensions/features/features.gni")
@@ skipping 24 matching lines @@
 
   # Hangout services is an extension that adds extra features to Hangouts.
   # It is enableable separately to facilitate testing.
   enable_hangout_services_extension = is_chrome_branded
 
   # 'Ok Google' hotwording is disabled by default. Set to true to enable. (This
   # will download a closed-source NaCl module at startup.) Chrome-branded
   # ChromeOS builds have this enabled by default.
   enable_hotwording = is_chrome_branded && is_chromeos
 
+  # Enables usage of the system-provided notification center.
+  enable_native_notifications =
+      is_android || is_mac || (is_desktop_linux && use_glib && use_gio)
+
   enable_one_click_signin =
       is_win || is_mac || (is_linux && !is_chromeos && !is_chromecast)
 
   # Set to true to bundle all the mash related mojo services into chrome.
   # Specify --mash to chrome to have chrome start the mash environment.
   enable_package_mash_services = is_chromeos
 
   enable_service_discovery = enable_mdns || is_mac
 
   # Enables use of the session service, which is enabled by default.
@@ skipping 39 matching lines @@
   "enable_plugins=$enable_plugins",
   "enable_print_preview=$enable_print_preview",
   "enable_printing=$_enable_printing",
   "enable_service_discovery=$enable_service_discovery",
   "enable_webrtc=$enable_webrtc",
   "enable_vr=$enable_vr",
   "mac_views_browser=$mac_views_browser",
   "safe_browsing_mode=$safe_browsing_mode",
   "use_vulcanize=$use_vulcanize",
 ]