Use file_util::GetHomeDir instead of getenv("HOME").

base/mime_util_xdg.cc

 // Copyright (c) 2009 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/mime_util.h"
 
 #include <gtk/gtk.h>
 #include <sys/time.h>
 #include <time.h>
 
@@ skipping 378 matching lines @@
 void AddXDGDataDir(const FilePath& dir) {
   if (!file_util::DirectoryExists(dir))
     return;
   TryAddIconDir(dir.Append("icons"));
   TryAddIconDir(dir.Append("pixmaps"));
 }
 
 // Add all the xdg icon directories.
 void InitIconDir() {
   Singleton<MimeUtilConstants>::get()->icon_dirs_->clear();
-  const char* home = getenv("HOME");
-  if (home) {
+  FilePath home = file_util::GetHomeDir();
+  if (!home.empty()) {
       FilePath legacy_data_dir(home);
       legacy_data_dir = legacy_data_dir.AppendASCII(".icons");
       if (file_util::DirectoryExists(legacy_data_dir))
         TryAddIconDir(legacy_data_dir);
   }
   const char* env = getenv("XDG_DATA_HOME");
   if (env) {
     AddXDGDataDir(FilePath(env));
-  } else if (home) {
+  } else if (!home.empty()) {
     FilePath local_data_dir(home);
     local_data_dir = local_data_dir.AppendASCII(".local");
     local_data_dir = local_data_dir.AppendASCII("share");
     AddXDGDataDir(local_data_dir);
   }
 
   env = getenv("XDG_DATA_DIRS");
   if (!env) {
     AddXDGDataDir(FilePath("/usr/local/share"));
     AddXDGDataDir(FilePath("/usr/share"));
@@ skipping 190 matching lines @@
     } else {
       icon_file = LookupIconInDefaultTheme(icon_names[i], size);
       if (!icon_file.empty())
         return icon_file;
     }
   }
   return FilePath();
 }
 
 }  // namespace mime_util