Add ContentSettingsProvider Interface.

chrome/browser/content_settings/content_identifier.h

+// Copyright (c) 2011 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_CONTENT_SETTINGS_CONTENT_IDENTIFIER_H_
+#define CHROME_BROWSER_CONTENT_SETTINGS_CONTENT_IDENTIFIER_H_
+#pragma once
+
+#include <string>
+
+#include "chrome/common/content_settings_types.h"
+
+namespace content_settings {
+
+typedef std::string ResourceIdentifier;
+
+class ContentIdentifier {
+ public:
+  ContentIdentifier(
+    const ContentSettingsType& content_type,
+    const ResourceIdentifier& resource_identifier);
+
+  bool operator==(const ContentIdentifier& other) const {
+    return (content_type_ == other.content_type_) &&
+           (resource_identifier_ == other.resource_identifier_);
+  }
+
+ private:
+  const ContentSettingsType content_type_;
+  const ResourceIdentifier resource_identifier_;
+};
+
+}  // namespace content_Settings
+
+#endif  // CHROME_BROWSER_CONTENT_SETTINGS_CONTENT_IDENTIFIER_H_