Created SerializableUserDataManager.

ios/web/public/serializable_user_data_manager.h

Index: ios/web/public/serializable_user_data_manager.h
diff --git a/ios/web/public/serializable_user_data_manager.h b/ios/web/public/serializable_user_data_manager.h
new file mode 100644
index 0000000000000000000000000000000000000000..cd7298637eede7519ccfb9b257b6c6b10eafc0f4
--- /dev/null
+++ b/ios/web/public/serializable_user_data_manager.h
@@ -0,0 +1,53 @@
+// 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 IOS_WEB_PUBLIC_SERIALIZABLE_USER_DATA_MANAGER_H_
+#define IOS_WEB_PUBLIC_SERIALIZABLE_USER_DATA_MANAGER_H_
+
+#import <Foundation/Foundation.h>
+#include <memory>
+
+namespace web {
+
+class WebState;
+
+// Class used to serialize values added to SerializableUserDataManager.
+class SerializableUserData {
+ public:
+  // Factory method.
+  static std::unique_ptr<SerializableUserData> Create();
+
+  // Encodes the data with |coder|.
+  virtual void Encode(NSCoder* coder) = 0;
+
+  // Decodes the data from |coder|.
+  virtual void Decode(NSCoder* coder) = 0;
+};
+
+// Class that can be used to add serializable user data to a WebState.
+class SerializableUserDataManager {
+ public:
+  // Returns the SerializableUserDataManager instance associated with
+  // |web_state|, instantiating one if necessary.
+  static SerializableUserDataManager* FromWebState(web::WebState* web_state);
+
+  // Adds |data| to the user data, allowing it to be encoded under |key|.
+  // |data| is expected to be non-nil.  If |key| has already been used

[Eugene But (OOO till 7-30), 2017/02/11 02:46:48]

Do you need to finish this sentence?

[kkhorimoto, 2017/02/11 03:19:49]

whoops! yes I did!

+  virtual void AddSerializableData(id<NSCoding> data, NSString* key) = 0;
+
+  // Returns the value that has been stored under |key|.
+  virtual id<NSCoding> GetValueForSerializationKey(NSString* key) = 0;
+
+  // Creates a SerializableUserData that can be used to encode the values added
+  // to the manager.
+  virtual std::unique_ptr<SerializableUserData> CreateSerializableUserData()
+      const = 0;
+
+  // Adds the values decoded from |data| to the manager.
+  virtual void AddSerializableUserData(SerializableUserData* data) = 0;
+};
+
+}  // namespace web
+
+#endif  // IOS_WEB_PUBLIC_SERIALIZABLE_USER_DATA_MANAGER_H_