Fix arrow position in action-style comboboxes on Linux in GTK theme mode.

ui/views/controls/combobox/combobox.h

 // Copyright (c) 2012 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 UI_VIEWS_CONTROLS_COMBOBOX_COMBOBOX_H_
 #define UI_VIEWS_CONTROLS_COMBOBOX_COMBOBOX_H_
 
 #include <string>
 
 #include "base/memory/weak_ptr.h"
@@ skipping 141 matching lines @@
   void OnPerformAction();
   void NotifyPerformAction();
   void AfterPerformAction();
 
   // Converts a menu command ID to a menu item index.
   int MenuCommandToIndex(int menu_command_id) const;
 
   int GetDisclosureArrowLeftPadding() const;
   int GetDisclosureArrowRightPadding() const;
 
+  // Returns the size of the disclosure arrow.
+  gfx::Size ArrowSize() const;
+
   // Handles the clicking event.
   void HandleClickEvent();
 
   // Our model. Not owned.
   ui::ComboboxModel* model_;
 
   // The visual style of this combobox.
   Style style_;
 
   // Our listener. Not owned. Notified when the selected index change.
@@ skipping 46 matching lines @@
 
   // Used for making calbacks.
   base::WeakPtrFactory<Combobox> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(Combobox);
 };
 
 }  // namespace views
 
 #endif  // UI_VIEWS_CONTROLS_COMBOBOX_COMBOBOX_H_