reland "CrOS: Fix appearance of notification toasts when sliding out via gesture"

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")
 import("//ui/vector_icons/vector_icons.gni")
 
 aggregate_vector_icons("message_center_vector_icons") {
@@ skipping 132 matching lines @@
         "views/notification_view.cc",
         "views/notification_view.h",
         "views/notifier_settings_view.cc",
         "views/notifier_settings_view.h",
         "views/padded_button.cc",
         "views/padded_button.h",
         "views/popup_alignment_delegate.cc",
         "views/popup_alignment_delegate.h",
         "views/proportional_image_view.cc",
         "views/proportional_image_view.h",
+        "views/slide_out_controller.cc",
+        "views/slide_out_controller.h",
         "views/toast_contents_view.cc",
         "views/toast_contents_view.h",
       ]
       deps += [
         "//ui/compositor",
         "//ui/events",
         "//ui/views",
       ]
     }
   } else {
@@ skipping 51 matching lines @@
     ":message_center",
     ":test_support",
     "//base",
     "//base/test:test_support",
     "//skia",
     "//testing/gmock",
     "//testing/gtest",
     "//ui/base",
     "//ui/base:test_support",
     "//ui/events",
+    "//ui/events:test_support",
     "//ui/gfx",
     "//ui/gfx/geometry",
     "//ui/gl",
     "//ui/gl:test_support",
     "//ui/resources",
     "//ui/resources:ui_test_pak",
     "//url",
   ]
 
   data_deps = [
@@ skipping 39 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",
       ]
     }
   }  # !is_ios && !is_android
 }