Replace string16 with base::string16.

chrome/browser/autocomplete/autocomplete_provider.h

Index: chrome/browser/autocomplete/autocomplete_provider.h
diff --git a/chrome/browser/autocomplete/autocomplete_provider.h b/chrome/browser/autocomplete/autocomplete_provider.h
index 02668b7a80cc68daf7486147082a96902bb4ae6b..76d289c04632ea3806e5cbf88fcbd4e757cb0da9 100644
--- a/chrome/browser/autocomplete/autocomplete_provider.h
+++ b/chrome/browser/autocomplete/autocomplete_provider.h
@@ -210,9 +210,9 @@ class AutocompleteProvider
   // A convenience function to call net::FormatUrl() with the current set of
   // "Accept Languages" when check_accept_lang is true.  Otherwise, it's called
   // with an empty list.
-  string16 StringForURLDisplay(const GURL& url,
-                               bool check_accept_lang,
-                               bool trim_http) const;
+  base::string16 StringForURLDisplay(const GURL& url,
+                                     bool check_accept_lang,
+                                     bool trim_http) const;
 
   // Returns the set of matches for the current query.
   const ACMatches& matches() const { return matches_; }