Move file_util_icu to base::i18n namespace

ui/base/l10n/l10n_util.cc

Index: ui/base/l10n/l10n_util.cc
diff --git a/ui/base/l10n/l10n_util.cc b/ui/base/l10n/l10n_util.cc
index 1dc036a2a0e52aae9c474886090452ac5c9a4840..55c4d04c393dfb55068134d728c5b6a790d4574b 100644
--- a/ui/base/l10n/l10n_util.cc
+++ b/ui/base/l10n/l10n_util.cc
@@ -225,7 +225,7 @@ bool IsLocalePartiallyPopulated(const std::string& locale_name) {
 bool IsLocaleAvailable(const std::string& locale) {
   // If locale has any illegal characters in it, we don't want to try to
   // load it because it may be pointing outside the locale data file directory.
-  if (!file_util::IsFilenameLegal(base::ASCIIToUTF16(locale)))
+  if (!base::i18n::IsFilenameLegal(base::ASCIIToUTF16(locale)))
     return false;
 
   // IsLocalePartiallyPopulated() can be called here for an early return w/o