linux: delete code that worked around gtk <2.18

views/controls/combobox/native_combobox_gtk.cc

 // Copyright (c) 2011 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 "views/controls/combobox/native_combobox_gtk.h"
 
 #include <gtk/gtk.h>
 
 #include <algorithm>
 
@@ skipping 162 matching lines @@
 
   // Get the menu item's label.
   std::string name;
   GList* children = gtk_container_get_children(GTK_CONTAINER(menu_item));
   for (GList* l = g_list_first(children); l != NULL; l = g_list_next(l)) {
     GtkWidget* child = static_cast<GtkWidget*>(l->data);
     if (GTK_IS_CELL_VIEW(child)) {
       GtkCellView* cell_view = GTK_CELL_VIEW(child);
       GtkTreePath* path = gtk_cell_view_get_displayed_row(cell_view);
       GtkTreeModel* model = NULL;
-#if GTK_CHECK_VERSION(2, 16, 0)
       model = gtk_cell_view_get_model(cell_view);
-#else
-      g_object_get(cell_view, "model", &model, NULL);
-#endif
       GtkTreeIter iter;
       if (model && gtk_tree_model_get_iter(model, &iter, path)) {
         GValue value = { 0 };
         gtk_tree_model_get_value(model, &iter, 0, &value);
         name = g_value_get_string(&value);
         break;
       }
     }
   }
 
@@ skipping 26 matching lines @@
 
 // static
 NativeComboboxWrapper* NativeComboboxWrapper::CreateWrapper(
     Combobox* combobox) {
   if (Widget::IsPureViews())
     return new NativeComboboxViews(combobox);
   return new NativeComboboxGtk(combobox);
 }
 
 }  // namespace views