Don't make |field_| first responder in SetSelectedRange() unless |model_| has_focus already.

chrome/browser/autocomplete/autocomplete_edit_view_mac.h

 // 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.
 
 #ifndef CHROME_BROWSER_AUTOCOMPLETE_AUTOCOMPLETE_EDIT_VIEW_MAC_H_
 #define CHROME_BROWSER_AUTOCOMPLETE_AUTOCOMPLETE_EDIT_VIEW_MAC_H_
 
 #import <Cocoa/Cocoa.h>
 
 #include "base/basictypes.h"
@@ skipping 93 matching lines @@
  private:
   // Returns the field's currently selected range.  Only valid if the
   // field has focus.
   NSRange GetSelectedRange() const;
 
   // Returns true if |field_| is first-responder in the window.  Used
   // in various DCHECKS to make sure code is running in appropriate
   // situations.
   bool IsFirstResponder() const;
 
-  // Grab focus if needed and set the selection to |range|.
+  // If |model_| believes it has focus, grab focus if needed and set
+  // the selection to |range|.  Otherwise does nothing.
   void SetSelectedRange(const NSRange range);
 
   // Update the field with |display_text| and highlight the host and
   // scheme (if it's an URL or URL-fragment).
   void UpdateAndStyleText(const std::wstring& display_text);
 
   scoped_ptr<AutocompleteEditModel> model_;
   scoped_ptr<AutocompletePopupViewMac> popup_view_;
 
   AutocompleteEditController* controller_;
@@ skipping 15 matching lines @@
 
   // Tracking state before and after a possible change for reporting
   // to model_.
   NSRange selection_before_change_;
   std::wstring text_before_change_;
 
   DISALLOW_COPY_AND_ASSIGN(AutocompleteEditViewMac);
 };
 
 #endif  // CHROME_BROWSER_AUTOCOMPLETE_AUTOCOMPLETE_EDIT_VIEW_MAC_H_