Remove private inheritance

It doesn't seem to have point.

Bug: None
Change-Id: I5e8131578c1191be9f0c27a5196425669470319c
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1626920
Commit-Queue: Sang Woo Ko <sangwoo108@chromium.org>
Reviewed-by: Peter Kasting <pkasting@chromium.org>
Cr-Commit-Position: refs/heads/master@{#662944}

chrome/browser/ui/views/omnibox/omnibox_result_view.h

@@ -41,7 +41,7 @@ class MenuRunner;
 }
 
 class OmniboxResultView : public views::View,
-                          private gfx::AnimationDelegate,
+                          public gfx::AnimationDelegate,
                           public views::ButtonListener,
                           public views::ContextMenuController,
                           public ui::SimpleMenuModel::Delegate {