Remove Downcasting RVContextMenuBase in ContextMenuDeleagate implementations.

athena/content/render_view_context_menu_impl.h

Index: athena/content/render_view_context_menu_impl.h
diff --git a/athena/content/render_view_context_menu_impl.h b/athena/content/render_view_context_menu_impl.h
index fa926ae720dca8d0a451c2f9ae31d49e59d9733e..8e5f49149d982ba8653f2cbc5101fe78b0a1f814 100644
--- a/athena/content/render_view_context_menu_impl.h
+++ b/athena/content/render_view_context_menu_impl.h
@@ -7,14 +7,18 @@
 
 #include "components/renderer_context_menu/render_view_context_menu_base.h"
 
-namespace views {
-class Widget;
+namespace aura {
+class Window;
 }
 
 namespace gfx {
 class Point;
 }
 
+namespace views {
+class Widget;
+}
+
 namespace athena {
 
 class RenderViewContextMenuImpl : public RenderViewContextMenuBase {
@@ -27,6 +31,9 @@ class RenderViewContextMenuImpl : public RenderViewContextMenuBase {
                  const gfx::Point& point,
                  ui::MenuSourceType type);
 
+  // RenderViewContextMenuBase:
+  virtual void Show() override;
+
  private:
   // RenderViewContextMenuBase:
   void InitMenu() override;
@@ -46,6 +53,9 @@ class RenderViewContextMenuImpl : public RenderViewContextMenuBase {
   bool IsCommandIdEnabled(int command_id) const override;
   void ExecuteCommand(int command_id, int event_flags) override;
 
+  aura::Window* GetActiveNativeView();
+  views::Widget* GetTopLevelWidget();
+
   DISALLOW_COPY_AND_ASSIGN(RenderViewContextMenuImpl);
 };