Add unittests of ArcCustomNotificationView

ui/arc/BUILD.gn

Index: ui/arc/BUILD.gn
diff --git a/ui/arc/BUILD.gn b/ui/arc/BUILD.gn
index 3139ee8bcee7443dddaf388543ebb959e362647e..fc1f4597a77d9ad51a1050566530f44021401a14 100644
--- a/ui/arc/BUILD.gn
+++ b/ui/arc/BUILD.gn
@@ -7,12 +7,13 @@ import("//testing/test.gni")
 
 static_library("arc") {
   sources = [
-    "notification/arc_custom_notification_item.cc",
-    "notification/arc_custom_notification_item.h",
     "notification/arc_custom_notification_view.cc",
     "notification/arc_custom_notification_view.h",
-    "notification/arc_notification_item.cc",
+    "notification/arc_notification_delegate.cc",
+    "notification/arc_notification_delegate.h",
     "notification/arc_notification_item.h",
+    "notification/arc_notification_item_impl.cc",
+    "notification/arc_notification_item_impl.h",
     "notification/arc_notification_manager.cc",
     "notification/arc_notification_manager.h",
     "notification/arc_notification_surface_manager.cc",
@@ -44,6 +45,7 @@ static_library("arc") {
 test("ui_arc_unittests") {
   testonly = true
   sources = [
+    "notification/arc_custom_notification_view_unittest.cc",
     "notification/arc_notification_manager_unittest.cc",
     "test/run_all_unittests.cc",
   ]
@@ -53,8 +55,13 @@ test("ui_arc_unittests") {
     "//base",
     "//base/test:test_support",
     "//components/arc:arc_test_support",
+    "//components/exo",
     "//mojo/edk/system",
     "//testing/gtest",
+    "//ui/base:test_support",
+    "//ui/gl",
+    "//ui/gl:test_support",
     "//ui/message_center:test_support",
+    "//ui/views:test_support",
   ]
 }