Clean up singleton implementation

fpdfsdk/javascript/JS_KeyValue.h

Index: fpdfsdk/javascript/JS_KeyValue.h
diff --git a/fpdfsdk/javascript/JS_KeyValue.h b/fpdfsdk/javascript/JS_KeyValue.h
new file mode 100644
index 0000000000000000000000000000000000000000..43f6687b8dc67c2b8765d034862e3e8450b8eed7
--- /dev/null
+++ b/fpdfsdk/javascript/JS_KeyValue.h
@@ -0,0 +1,46 @@
+// Copyright 2016 PDFium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com
+
+#ifndef FPDFSDK_JAVASCRIPT_JS_KEYVALUE_H_
+#define FPDFSDK_JAVASCRIPT_JS_KEYVALUE_H_
+
+#include <memory>
+#include <vector>
+
+#include "core/fxcrt/include/fx_basic.h"
+
+enum class JS_GlobalDataType { NUMBER = 0, BOOLEAN, STRING, OBJECT, NULLOBJ };
+
+class CJS_KeyValue;
+
+class CJS_GlobalVariableArray {
+ public:
+  CJS_GlobalVariableArray();
+  ~CJS_GlobalVariableArray();
+
+  void Add(CJS_KeyValue* p);
+  int Count() const;
+  CJS_KeyValue* GetAt(int index) const;
+  void Copy(const CJS_GlobalVariableArray& array);
+
+ private:
+  std::vector<std::unique_ptr<CJS_KeyValue>> m_Array;
+};
+
+class CJS_KeyValue {
+ public:
+  CJS_KeyValue();
+  ~CJS_KeyValue();
+
+  CFX_ByteString sKey;
+  JS_GlobalDataType nType;
+  double dData;
+  bool bData;
+  CFX_ByteString sData;
+  CJS_GlobalVariableArray objData;
+};
+
+#endif  // FPDFSDK_JAVASCRIPT_JS_KEYVALUE_H_