ui/base/models: Add protected virtual destructor to ComboboxModel.

The use of a protected virtual destructor is to prevent the destruction of a
derived object via a base-class pointer.

That's it, ComboboxModel should only be deleted through derived class.

Example 1:

class FooComboboxModel : public ComboboxModel {
};

ComboboxModel* model = new FooComboboxModel;
delete model;  // It should prevent this situation!

Also, a protected virtual destructor makes it clear that someone else owns the
object.

Example 2:

class Foo {
 public:
  void SetModel(ComboboxModel* model);
};

If you see that the model has a protected destructor, you know Foo doesn't own
|model|.

R=sky@chromium.org

Review URL: https://chromiumcodereview.appspot.com/9817007

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@128132 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 4 insertions, 4 deletions

diff --git a/ui/views/controls/combobox/native_combobox_views_unittest.cc b/ui/views/controls/combobox/native_combobox_views_unittest.cc
index caa1275..2474c4a 100644
--- a/ui/views/controls/combobox/native_combobox_views_unittest.cc
+++ b/ui/views/controls/combobox/native_combobox_views_unittest.cc
@@ -135,14 +135,14 @@ class NativeComboboxViewsTest : public ViewsTestBase {
   // We need widget to populate wrapper class.
   Widget* widget_;
 
-  // combobox_ will be allocated InitCombobox() and then owned by widget_.
+  // |combobox_| will be allocated InitCombobox() and then owned by |widget_|.
   TestCombobox* combobox_;
 
-  // combobox_view_ is the pointer to the pure Views interface of combobox_.
+  // |combobox_view_| is the pointer to the pure Views interface of |combobox_|.
   NativeComboboxViews* combobox_view_;
 
-  // Combobox does not take ownership of model_, which needs to be scoped.
-  scoped_ptr<ui::ComboboxModel> model_;
+  // Combobox does not take ownership of the model, hence it needs to be scoped.
+  scoped_ptr<TestComboboxModel> model_;
 
   // For testing input method related behaviors.
   MockInputMethod* input_method_;