Add ContextMenuSourceType to views::ContextMenuController::ShowContextMenuForView.

ui/base/ui_base_types.cc

+// 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.
+
+#include "ui/base/ui_base_types.h"
+
+#include "ui/base/events/event.h"
+
+namespace ui {
+
+MenuSourceType GetMenuSourceTypeForEvent(const ui::Event& event) {
+  ui::MenuSourceType source_type = ui::MENU_SOURCE_MOUSE;
+  if (event.IsKeyEvent())
+    source_type = ui::MENU_SOURCE_KEYBOARD;
+  if (event.IsTouchEvent() || event.IsGestureEvent())
+    source_type = ui::MENU_SOURCE_TOUCH;
+  return source_type;
+}
+
+}  // namespace ui