Update some uses of UTF conversions in chrome/browser to use the base:: namespace.

chrome/browser/ui/app_list/search/webstore/webstore_provider.cc

Index: chrome/browser/ui/app_list/search/webstore/webstore_provider.cc
diff --git a/chrome/browser/ui/app_list/search/webstore/webstore_provider.cc b/chrome/browser/ui/app_list/search/webstore/webstore_provider.cc
index 88a70082db3837a94eb32b61e228a97477ee0ae6..e52f98125698c2b76c8df88885dd51a4ba120930 100644
--- a/chrome/browser/ui/app_list/search/webstore/webstore_provider.cc
+++ b/chrome/browser/ui/app_list/search/webstore/webstore_provider.cc
@@ -52,7 +52,7 @@ void WebstoreProvider::Start(const base::string16& query) {
     return;
   }
 
-  query_ = UTF16ToUTF8(query);
+  query_ = base::UTF16ToUTF8(query);
   const CacheResult result = cache_->Get(WebserviceCache::WEBSTORE, query_);
   if (result.second) {
     ProcessWebstoreSearchResults(result.second);