Remove wstring from autocomplete.

chrome/browser/autocomplete/autocomplete_popup_view_mac.h

Index: chrome/browser/autocomplete/autocomplete_popup_view_mac.h
===================================================================
--- chrome/browser/autocomplete/autocomplete_popup_view_mac.h	(revision 72388)
+++ chrome/browser/autocomplete/autocomplete_popup_view_mac.h	(working copy)
@@ -102,7 +102,7 @@
   // and description cases.  Returns NSMutableAttributedString as a
   // convenience for MatchText().
   static NSMutableAttributedString* DecorateMatchedString(
-      const std::wstring &matchString,
+      const string16 &matchString,
       const AutocompleteMatch::ACMatchClassifications &classifications,
       NSColor* textColor, NSColor* dimTextColor, gfx::Font& font);
 
@@ -114,7 +114,7 @@
   // cleaner.
   static NSMutableAttributedString* ElideString(
       NSMutableAttributedString* aString,
-      const std::wstring originalString,
+      const string16 originalString,
       const gfx::Font& font,
       const float cellWidth);