Apply system style to High Contrast Mode notification.

In new-style notification system notification has different style from
other notifications such as web notifications.
* The context header shous the title "Chrome OS system".
* The context header has accent color.
* New MD icon is used.
This CL applies the system style to High Contrast Mode notification.

TEST=manual
BUG=751024

Change-Id: I7ab022e5b7fcd7e2807ca5327e196c1e2f6b3e84
Reviewed-on: https://chromium-review.googlesource.com/637058
Commit-Queue: Tetsui Ohkubo <tetsui@chromium.org>
Reviewed-by: James Cook <jamescook@chromium.org>
Cr-Commit-Position: refs/heads/master@{#498030}

ash/accelerators/accelerator_controller.cc

@@ -78,6 +78,7 @@ namespace {
 using base::UserMetricsAction;
 using chromeos::input_method::InputMethodManager;
 using message_center::Notification;
+using message_center::SystemNotificationWarningLevel;
 
 // Identifier for the high contrast toggle accelerator notification.
 const char kHighContrastToggleAccelNotificationId[] =
@@ -717,15 +718,21 @@ void HandleToggleHighContrast() {
   // Show a notification so the user knows that this accelerator toggled
   // high contrast mode, and that they can press it again to toggle back.
   // The message center automatically only shows this once per session.
-  std::unique_ptr<Notification> notification(new Notification(
-      message_center::NOTIFICATION_TYPE_SIMPLE,
-      kHighContrastToggleAccelNotificationId, base::string16() /* title */,
-      l10n_util::GetStringUTF16(IDS_HIGH_CONTRAST_ACCEL_MSG),
-      gfx::Image(CreateVectorIcon(kSystemMenuAccessibilityIcon, SK_ColorBLACK)),
-      base::string16() /* display source */, GURL(),
-      message_center::NotifierId(message_center::NotifierId::SYSTEM_COMPONENT,
-                                 system_notifier::kNotifierAccessibility),
-      message_center::RichNotificationData(), nullptr));
+  std::unique_ptr<Notification> notification =
+      system_notifier::CreateSystemNotification(
+          message_center::NOTIFICATION_TYPE_SIMPLE,
+          kHighContrastToggleAccelNotificationId,
+          l10n_util::GetStringUTF16(IDS_HIGH_CONTRAST_ACCEL_TITLE),
+          l10n_util::GetStringUTF16(IDS_HIGH_CONTRAST_ACCEL_MSG),
+          gfx::Image(
+              CreateVectorIcon(kSystemMenuAccessibilityIcon, SK_ColorBLACK)),
+          base::string16() /* display source */, GURL(),
+          message_center::NotifierId(
+              message_center::NotifierId::SYSTEM_COMPONENT,
+              system_notifier::kNotifierAccessibility),
+          message_center::RichNotificationData(), nullptr,
+          kNotificationAccessibilityIcon,
+          SystemNotificationWarningLevel::NORMAL);
   message_center::MessageCenter::Get()->AddNotification(
       std::move(notification));
 

ash/accelerators/accelerator_controller_unittest.cc

@@ -1326,6 +1326,8 @@ TEST_F(DeprecatedAcceleratorTester, TestNewAccelerators) {
     // screen before we proceed testing the rest of accelerators.
     ResetStateIfNeeded();
   }
+
+  RemoveAllNotifications();
 }
 
 }  // namespace ash

ash/ash_strings.grd

@@ -1068,6 +1068,10 @@ This file contains the strings for ash.
       </message>
 
       <!-- Notification that an accelerator was pressed, so the user knows how to toggle it back -->
+      <message name="IDS_HIGH_CONTRAST_ACCEL_TITLE"
+               desc="Notification title to tell users that they just pressed the Search+Shift+H shortcut to toggle High Contrast Mode, and that pressing it again will toggle it off.">
+        High Contrast Mode
+      </message>
       <message name="IDS_HIGH_CONTRAST_ACCEL_MSG"
                desc="Notification message to tell users that they just pressed the Search+Shift+H shortcut to toggle High Contrast Mode, and that pressing it again will toggle it off.">
         High Contrast Mode enabled. Press Ctrl+Search+H again to toggle it off.