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

base/file_version_info_unittest.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.h"
 #include "base/files/file_path.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/path_service.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
@@ skipping 75 matching lines @@
   };
 
   const bool kExpected[] = {
     true,
     false,
   };
 
   // Test consistency check.
   ASSERT_EQ(arraysize(kDLLNames), arraysize(kExpected));
 
-  for (int i = 0; i < arraysize(kDLLNames); ++i) {
+  for (size_t i = 0; i < arraysize(kDLLNames); ++i) {
     FilePath dll_path = GetTestDataPath();
     dll_path = dll_path.Append(kDLLNames[i]);
 
     scoped_ptr<FileVersionInfo> version_info(
         FileVersionInfo::CreateFileVersionInfo(dll_path));
 
     EXPECT_EQ(kExpected[i], version_info->is_official_build());
   }
 }
 #endif
@@ skipping 21 matching lines @@
   EXPECT_TRUE(version_info_win->GetValue(L"Custom prop 3",  &str));
   EXPECT_EQ(L"1600 Amphitheatre Parkway Mountain View, CA 94043", str);
   EXPECT_EQ(L"1600 Amphitheatre Parkway Mountain View, CA 94043",
             version_info_win->GetStringValue(L"Custom prop 3"));
 
   // Test an non-existing property.
   EXPECT_FALSE(version_info_win->GetValue(L"Unknown property",  &str));
   EXPECT_EQ(L"", version_info_win->GetStringValue(L"Unknown property"));
 }
 #endif