Cleanup some PPAPI proxy code.

ppapi/proxy/flash_font_file_resource.h

 // 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 PPAPI_PROXY_FLASH_FONT_FILE_RESOURCE_H_
 #define PPAPI_PROXY_FLASH_FONT_FILE_RESOURCE_H_
 
-#include <map>
 #include <string>
 
-#include "base/basictypes.h"
-#include "base/compiler_specific.h"
-#include "base/memory/linked_ptr.h"
+#include "base/containers/scoped_ptr_hash_map.h"
 #include "ppapi/c/private/pp_private_font_charset.h"
 #include "ppapi/proxy/plugin_resource.h"
 #include "ppapi/proxy/serialized_structs.h"
 #include "ppapi/thunk/ppb_flash_font_file_api.h"
 
 struct PP_BrowserFont_Trusted_Description;
 
 namespace ppapi {
 namespace proxy {
 
@@ skipping 11 matching lines @@
   thunk::PPB_Flash_FontFile_API* AsPPB_Flash_FontFile_API() override;
 
   // PPB_Flash_FontFile_API.
   PP_Bool GetFontTable(uint32_t table,
                        void* output,
                        uint32_t* output_length) override;
 
  private:
   // Sees if we have a cache of the font table and returns a pointer to it.
   // Returns NULL if we don't have it.
-  std::string* GetFontTable(uint32_t table) const;
+  const std::string* GetFontTable(uint32_t table) const;
 
-  std::string* AddFontTable(uint32_t table, const std::string& contents);
+  const std::string* AddFontTable(uint32_t table, const std::string& contents);
 
-  typedef std::map<uint32_t, linked_ptr<std::string> > FontTableMap;
+  using FontTableMap =
+      base::ScopedPtrHashMap<uint32_t, scoped_ptr<std::string>>;
   FontTableMap font_tables_;
 
   SerializedFontDescription description_;
-  PP_PrivateFontCharset charset_;
+  const PP_PrivateFontCharset charset_;
 
   DISALLOW_COPY_AND_ASSIGN(FlashFontFileResource);
 };
 
 }  // namespace proxy
 }  // namespace ppapi
 
 #endif  // PPAPI_PROXY_FLASH_FONT_FILE_RESOURCE_H_