Transfer responsibility for providing a close button for a notification to each implementation of M…

ui/message_center/BUILD.gn

 # 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.
 
 import("//build/config/features.gni")
 import("//build/config/ui.gni")
 import("//testing/test.gni")
 
 # TODO(msw|mukai|dewittj): Move ash-specific files: crbug.com/585175
 component("message_center") {
@@ skipping 80 matching lines @@
     }
 
     # On Mac, toolkit-views builds still use the Cocoa UI. Keep this in sync
     # with message_center_unittests below.
     if (toolkit_views && !is_mac) {
       sources += [
         "notification_delegate_views.cc",
         "views/bounded_label.cc",
         "views/bounded_label.h",
         "views/constants.h",
+        "views/custom_notification_content_view_delegate.cc",
+        "views/custom_notification_content_view_delegate.h",
         "views/custom_notification_view.cc",
         "views/custom_notification_view.h",
         "views/desktop_popup_alignment_delegate.cc",
         "views/desktop_popup_alignment_delegate.h",
         "views/message_bubble_base.cc",
         "views/message_bubble_base.h",
         "views/message_center_bubble.cc",
         "views/message_center_bubble.h",
         "views/message_center_button_bar.cc",
         "views/message_center_button_bar.h",
@@ skipping 144 matching lines @@
     if (!is_ios) {
       sources += [ "mojo/struct_traits_unittest.cc" ]
       deps += [
         "//mojo/edk/system",
         "//ui/gfx:test_support",
         "//ui/message_center/mojo:test_interfaces",
       ]
     }
   }  # enable_notifications && !is_android
 }