[Android] Adding content settings provider for notification channels

chrome/browser/notifications/notification_content_settings_provider_android.h

+// Copyright 2017 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_CONTENT_SETTINGS_PROVIDER_ANDROID_H_
+#define CHROME_BROWSER_NOTIFICATIONS_NOTIFICATION_CONTENT_SETTINGS_PROVIDER_ANDROID_H_
+
+#include <string>
+
+#include "base/macros.h"
+#include "components/content_settings/core/browser/content_settings_observable_provider.h"
+#include "components/content_settings/core/browser/content_settings_observer.h"
+#include "components/content_settings/core/browser/content_settings_rule.h"
+#include "components/content_settings/core/common/content_settings.h"
+#include "components/content_settings/core/common/content_settings_types.h"
+#include "components/keyed_service/core/keyed_service.h"
+
+// This class provides notification content settings from system notification
+// channels on Android O+. This provider takes precedence over normal content

[raymes, 2017/05/17 03:13:39]

nit: normal content settings->pref provided content settings 

(or something to that effect)

[awdf, 2017/05/17 17:14:41]

Done.

+// settings, but defers to supervised user and policy settings - see ordering
+// of the ProviderType enum values in HostContentSettingsMap.
+class NotificationContentSettingsProviderAndroid
+    : public content_settings::ObservableProvider {
+ public:
+  NotificationContentSettingsProviderAndroid();
+  ~NotificationContentSettingsProviderAndroid() override;
+
+  // ProviderInterface methods:
+  std::unique_ptr<content_settings::RuleIterator> GetRuleIterator(
+      ContentSettingsType content_type,
+      const content_settings::ResourceIdentifier& resource_identifier,
+      bool incognito) const override;
+
+  bool SetWebsiteSetting(
+      const ContentSettingsPattern& primary_pattern,
+      const ContentSettingsPattern& secondary_pattern,
+      ContentSettingsType content_type,
+      const content_settings::ResourceIdentifier& resource_identifier,
+      base::Value* value) override;
+
+  void ClearAllContentSettingsRules(ContentSettingsType content_type) override;
+
+  void ShutdownOnUIThread() override;
+
+ private:
+  bool should_use_channels_;
+
+  DISALLOW_COPY_AND_ASSIGN(NotificationContentSettingsProviderAndroid);
+};
+
+#endif  // CHROME_BROWSER_NOTIFICATIONS_NOTIFICATION_CONTENT_SETTINGS_PROVIDER_ANDROID_H_