Add the button style for combobox

ui/views/controls/menu/menu_runner_handler.h

Index: ui/views/controls/menu/menu_runner_handler.h
diff --git a/ui/views/controls/menu/menu_runner_handler.h b/ui/views/controls/menu/menu_runner_handler.h
new file mode 100644
index 0000000000000000000000000000000000000000..46f801af685795f76d5dc985e542450bda0768df
--- /dev/null
+++ b/ui/views/controls/menu/menu_runner_handler.h
@@ -0,0 +1,31 @@
+// Copyright 2013 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_MENU_MENU_RUNNER_HANDLER_H_
+#define UI_VIEWS_CONTROLS_MENU_MENU_RUNNER_HANDLER_H_
+
+#include "base/basictypes.h"
+#include "ui/views/controls/menu/menu_item_view.h"
+
+namespace views {
+
+class MenuButton;
+class Widget;
+
+// Used internally by MenuRunner to show the menu. Can be set in tests (see
+// MenuRunnerTestApi) for mocking running of the menu.
+class VIEWS_EXPORT MenuRunnerHandler {
+ public:
+  virtual ~MenuRunnerHandler() {}
+  virtual MenuRunner::RunResult RunMenuAt(Widget* parent,
+                                          MenuButton* button,
+                                          const gfx::Rect& bounds,
+                                          MenuItemView::AnchorPosition anchor,
+                                          ui::MenuSourceType source_type,
+                                          int32 types) = 0;
+};
+
+}  // namespace views
+
+#endif  // UI_VIEWS_CONTROLS_MENU_MENU_RUNNER_HANDLER_H_