Support persistent incognito preferences

chrome/browser/extensions/extension_prefs_scope.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_EXTENSIONS_EXTENSION_PREFS_SCOPE_H_
+#define CHROME_BROWSER_EXTENSIONS_EXTENSION_PREFS_SCOPE_H_
+#pragma once
+
+namespace extension_prefs_scope {
+
+// Scope for a preference.
+enum Scope {
+  // Regular profile.
+  kRegular,
+  // Incognito profile; preference is persisted to disk and remains active
+  // after a browser restart.
+  kIncognitoPersistent,
+  // TODO(battre): add kIncognitoSession
+};
+
+}  // extension_prefs_scope
+
+#endif  // CHROME_BROWSER_EXTENSIONS_EXTENSION_PREFS_SCOPE_H_