Remove OwnPtr from Blink.

third_party/WebKit/Source/web/StorageClientImpl.h

 // Copyright 2014 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 StorageClientImpl_h
 #define StorageClientImpl_h
 
 #include "modules/storage/StorageClient.h"
+#include <memory>
 
 namespace blink {
 
 class WebViewImpl;
 
 class StorageClientImpl : public StorageClient {
 public:
     explicit StorageClientImpl(WebViewImpl*);
 
-    PassOwnPtr<StorageNamespace> createSessionStorageNamespace() override;
+    std::unique_ptr<StorageNamespace> createSessionStorageNamespace() override;
     bool canAccessStorage(LocalFrame*, StorageType) const override;
 
 private:
     WebViewImpl* m_webView;
 };
 
 } // namespace blink
 
 #endif // StorageClientImpl_h