Revert 72380 - Remove wstring from autocomplete....

chrome/browser/autocomplete/history_provider.h

 // Copyright (c) 2010 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.
 
 #ifndef CHROME_BROWSER_AUTOCOMPLETE_HISTORY_PROVIDER_H_
 #define CHROME_BROWSER_AUTOCOMPLETE_HISTORY_PROVIDER_H_
 #pragma once
 
 #include "base/compiler_specific.h"
 #include "chrome/browser/autocomplete/autocomplete.h"
@@ skipping 26 matching lines @@
   // Fixes up user URL input to make it more possible to match against.  Among
   // many other things, this takes care of the following:
   // * Prepending file:// to file URLs
   // * Converting drive letters in file URLs to uppercase
   // * Converting case-insensitive parts of URLs (like the scheme and domain)
   //   to lowercase
   // * Convert spaces to %20s
   // Note that we don't do this in AutocompleteInput's constructor, because if
   // e.g. we convert a Unicode hostname to punycode, other providers will show
   // output that surprises the user ("Search Google for xn--6ca.com").
-  static string16 FixupUserInput(const AutocompleteInput& input);
+  static std::wstring FixupUserInput(const AutocompleteInput& input);
 
   // Trims "http:" and up to two subsequent slashes from |url|.  Returns the
   // number of characters that were trimmed.
   // NOTE: For a view-source: URL, this will trim from after "view-source:" and
   // return 0.
-  static size_t TrimHttpPrefix(string16* url);
+  static size_t TrimHttpPrefix(std::wstring* url);
 };
 
 #endif  // CHROME_BROWSER_AUTOCOMPLETE_HISTORY_PROVIDER_H_