Introduce a new API to handle native notification clicks

chrome/browser/notifications/notification_operation_common.h

+// Copyright 2016 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.
+
+#ifndef CHROME_BROWSER_NOTIFICATIONS_NOTIFICATION_OPERATION_COMMON_H_
+#define CHROME_BROWSER_NOTIFICATIONS_NOTIFICATION_OPERATION_COMMON_H_
+
+// A series of common operations for both in page and persistent notification
+namespace content {
+class BrowserContext;
+}  // namespace content
+
+namespace notification_operation_common {
+
+// Possible kinds of notifications
+enum NotificationHandlerType {
+  PERSISTENT_NOTIFICATION = 0,
+  INPAGE_NOTIFICATION = 1,
+  NOTIFICATION_HANDLER_TYPE_LAST = INPAGE_NOTIFICATION

[Peter Beverloo, 2016/06/29 00:23:16]

Why do you call this _LAST, but the enum eight lines down _MAX?

[Miguel Garcia, 2016/07/05 13:54:50]

Done.

+};
+
+// Things a user can do to a notification.
+enum NotificationOperation {
+  NOTIFICATION_CLICK = 0,
+  NOTIFICATION_CLOSE = 1,
+  NOTIFICATION_SETTINGS = 2,
+  NOTIFICATION_OPERATION_MAX = NOTIFICATION_SETTINGS
+};
+
+// Open the Notification settings screen when clicking the right button.
+void OpenNotificationSettings(content::BrowserContext* browser_context);
+
+}  // namespace notification_operation_common
+
+#endif  // CHROME_BROWSER_NOTIFICATIONS_NOTIFICATION_OPERATION_COMMON_H_