Remove a deprecated wstring ToLower function.

chrome/browser/autocomplete/search_provider.cc

Index: chrome/browser/autocomplete/search_provider.cc
diff --git a/chrome/browser/autocomplete/search_provider.cc b/chrome/browser/autocomplete/search_provider.cc
index 08dc01cdabc404b490fa1f13c2bd4aa313440d13..77359c7fe48de1494b4d12a31b22454daf712fcc 100644
--- a/chrome/browser/autocomplete/search_provider.cc
+++ b/chrome/browser/autocomplete/search_provider.cc
@@ -716,7 +716,7 @@ void SearchProvider::AddMatchToMap(const std::wstring& query_string,
   // NOTE: Keep this ToLower() call in sync with url_database.cc.
   const std::pair<MatchMap::iterator, bool> i = map->insert(
       std::pair<std::wstring, AutocompleteMatch>(
-      l10n_util::ToLower(query_string), match));
+      UTF16ToWide(l10n_util::ToLower(WideToUTF16(query_string))), match));
   // NOTE: We purposefully do a direct relevance comparison here instead of
   // using AutocompleteMatch::MoreRelevant(), so that we'll prefer "items added
   // first" rather than "items alphabetically first" when the scores are equal.