Split off CPDF_Parser and CPDF_SimpleParser into .h/.cpp files

core/include/fpdfapi/cpdf_simple_parser.h

+// 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 CORE_INCLUDE_FPDFAPI_CPDF_SIMPLE_PARSER_H_
+#define CORE_INCLUDE_FPDFAPI_CPDF_SIMPLE_PARSER_H_
+
+#include "core/include/fxcrt/fx_string.h"
+#include "core/include/fxcrt/fx_system.h"
+
+class CPDF_SimpleParser {
+ public:
+  CPDF_SimpleParser(const uint8_t* pData, FX_DWORD dwSize);
+  CPDF_SimpleParser(const CFX_ByteStringC& str);
+
+  CFX_ByteStringC GetWord();
+
+  // Find the token and its |nParams| parameters from the start of data,
+  // and move the current position to the start of those parameters.
+  bool FindTagParamFromStart(const CFX_ByteStringC& token, int nParams);
+
+  // For testing only.
+  FX_DWORD GetCurPos() const { return m_dwCurPos; }
+
+ private:
+  void ParseWord(const uint8_t*& pStart, FX_DWORD& dwSize);
+
+  const uint8_t* m_pData;
+  FX_DWORD m_dwSize;
+  FX_DWORD m_dwCurPos;
+};
+
+#endif  // CORE_INCLUDE_FPDFAPI_CPDF_SIMPLE_PARSER_H_