Allow script to request durable storage permission (chrome side)

chrome/browser/durable_storage_permission_context.h

Index: chrome/browser/durable_storage_permission_context.h
diff --git a/chrome/browser/durable_storage_permission_context.h b/chrome/browser/durable_storage_permission_context.h
new file mode 100644
index 0000000000000000000000000000000000000000..eaa0912f762845f456aaa2ca1b500b8708259681
--- /dev/null
+++ b/chrome/browser/durable_storage_permission_context.h
@@ -0,0 +1,24 @@
+// Copyright 2015 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_DURABLE_STORAGE_PERMISSION_CONTEXT_H_
+#define CHROME_BROWSER_DURABLE_STORAGE_PERMISSION_CONTEXT_H_
+
+#include "chrome/browser/content_settings/permission_context_base.h"
+
+class GURL;
+class PermissionRequestID;
+
+class DurableStoragePermissionContext : public PermissionContextBase {
+ public:
+  explicit DurableStoragePermissionContext(Profile* profile);
+  ~DurableStoragePermissionContext() override;
+  bool IsRestrictedToSecureOrigins() const override;
+
+ private:
+
+  DISALLOW_COPY_AND_ASSIGN(DurableStoragePermissionContext);
+};
+
+#endif  // CHROME_BROWSER_DURABLE_STORAGE_PERMISSION_CONTEXT_H_