clang/win: Let some chromium_code targets build with -Wextra.

base/file_version_info_win.cc

 // Copyright (c) 2011 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.
 
 #include "base/file_version_info_win.h"
 
 #include <windows.h>
 
 #include "base/file_version_info.h"
 #include "base/files/file_path.h"
@@ skipping 131 matching lines @@
   return GetStringValue(L"LastChange");
 }
 
 bool FileVersionInfoWin::is_official_build() {
   return (GetStringValue(L"Official Build").compare(L"1") == 0);
 }
 
 bool FileVersionInfoWin::GetValue(const wchar_t* name,
                                   std::wstring* value_str) {
   WORD lang_codepage[8];
-  int i = 0;
+  size_t i = 0;
   // Use the language and codepage from the DLL.
   lang_codepage[i++] = language_;
   lang_codepage[i++] = code_page_;
   // Use the default language and codepage from the DLL.
   lang_codepage[i++] = ::GetUserDefaultLangID();
   lang_codepage[i++] = code_page_;
   // Use the language from the DLL and Latin codepage (most common).
   lang_codepage[i++] = language_;
   lang_codepage[i++] = 1252;
   // Use the default language and Latin codepage (most common).
@@ skipping 18 matching lines @@
   return false;
 }
 
 std::wstring FileVersionInfoWin::GetStringValue(const wchar_t* name) {
   std::wstring str;
   if (GetValue(name, &str))
     return str;
   else
     return L"";
 }