Gtk3: Add foreign-drawing for menus

chrome/browser/ui/libgtkui/native_theme_gtk3.h

Index: chrome/browser/ui/libgtkui/native_theme_gtk3.h
diff --git a/chrome/browser/ui/libgtkui/native_theme_gtk3.h b/chrome/browser/ui/libgtkui/native_theme_gtk3.h
index 867a09b905150be407c5a34c9cd5bb54d50be281..1826e778a5386b2a57617612de156ba3ff176ac9 100644
--- a/chrome/browser/ui/libgtkui/native_theme_gtk3.h
+++ b/chrome/browser/ui/libgtkui/native_theme_gtk3.h
@@ -19,6 +19,15 @@ class NativeThemeGtk3 : public ui::NativeThemeBase {
 
   // Overridden from ui::NativeThemeBase:
   SkColor GetSystemColor(ColorId color_id) const override;
+  void PaintMenuPopupBackground(
+      SkCanvas* canvas,
+      const gfx::Size& size,
+      const MenuBackgroundExtraParams& menu_background) const override;
+  void PaintMenuItemBackground(
+      SkCanvas* canvas,
+      State state,
+      const gfx::Rect& rect,
+      const MenuItemExtraParams& menu_item) const override;
 
  private:
   NativeThemeGtk3();