Use WebIDBKeyPath type in WebKit API, implement IndexedDBKeyPath type.

content/common/indexed_db/indexed_db_key_path.h

Index: content/common/indexed_db/indexed_db_key_path.h
diff --git a/content/common/indexed_db/indexed_db_key_path.h b/content/common/indexed_db/indexed_db_key_path.h
new file mode 100644
index 0000000000000000000000000000000000000000..5c09d56adc5a815eeafd10c751ba781925c4b6f3
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+++ b/content/common/indexed_db/indexed_db_key_path.h
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+// Copyright (c) 2012 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 CONTENT_COMMON_INDEXED_DB_INDEXED_DB_KEY_PATH_H_
+#define CONTENT_COMMON_INDEXED_DB_INDEXED_DB_KEY_PATH_H_
+#pragma once
+
+#include <vector>
+
+#include "base/basictypes.h"
+#include "base/string16.h"
+#include "content/common/content_export.h"
+#include "third_party/WebKit/Source/WebKit/chromium/public/WebIDBKeyPath.h"
+
+namespace content {
+
+class CONTENT_EXPORT IndexedDBKeyPath {
+ public:
+  IndexedDBKeyPath();  // Defaults to WebKit::WebIDBKeyPath::NullType.
+  explicit IndexedDBKeyPath(const WebKit::WebIDBKeyPath& keyPath);
+  ~IndexedDBKeyPath();
+
+  void SetNull();
+  void SetArray(const std::vector<string16>& array);
+  void SetString(const string16& string);
+  void Set(const WebKit::WebIDBKeyPath& key);
+
+  bool IsValid() const;
+
+  WebKit::WebIDBKeyPath::Type type() const { return type_; }
+  const std::vector<string16>& array() const { return array_; }
+  const string16& string() const { return string_; }
+
+  operator WebKit::WebIDBKeyPath() const;
+
+ private:
+  WebKit::WebIDBKeyPath::Type type_;
+  std::vector<string16> array_;
+  string16 string_;
+};
+
+}  // namespace content
+
+#endif  // CONTENT_COMMON_INDEXED_DB_INDEXED_DB_KEY_PATH_H_