Making the focus remembering across tab switch work.

chrome/browser/autocomplete/autocomplete_edit_view_mac.mm

 // Copyright (c) 2009 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.
 
 #include "chrome/browser/autocomplete/autocomplete_edit_view_mac.h"
 
 #include <Carbon/Carbon.h>  // kVK_Return
 #include "app/gfx/font.h"
 #include "app/resource_bundle.h"
 #include "base/clipboard.h"
@@ skipping 344 matching lines @@
   //
   // One option would seem to be to check for a non-nil field
   // editor, and check it's selected range against its length.
   model_->StartAutocomplete(false);
 }
 
 void AutocompleteEditViewMac::ClosePopup() {
   popup_view_->GetModel()->StopAutocomplete();
 }
 
+void AutocompleteEditViewMac::SetFocus() {
+}
+
 void AutocompleteEditViewMac::SetText(const std::wstring& display_text) {
   NSString* ss = base::SysWideToNSString(display_text);
   NSMutableAttributedString* as =
       [[[NSMutableAttributedString alloc] initWithString:ss] autorelease];
   NSFont* font = ResourceBundle::GetSharedInstance().GetFont(
       ResourceBundle::BaseFont).nativeFont();
   [as addAttribute:NSFontAttributeName value:font
              range:NSMakeRange(0, [as length])];
 
   url_parse::Parsed parts;
@@ skipping 469 matching lines @@
 // prepended and ".com" appended.  This calls down to
 // AutocompleteEditModel::OnControlKeyChanged() so that it can change
 // the popup to reflect this.  See autocomplete_edit.cc
 // OnControlKeyChanged() and OnAfterPossibleChange().
 - (void)control:(NSControl*)control flagsChanged:(NSEvent*)theEvent {
   bool controlFlag = ([theEvent modifierFlags]&NSControlKeyMask) != 0;
   edit_view_->OnControlKeyChanged(controlFlag);
 }
 
 @end