Removed unimplemented and unused method.

Change-Id: I40a49793b9db01ae8b6497c38b09ab420cd56a47
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1895754
Auto-Submit: Dana Fried <dfried@chromium.org>
Commit-Queue: Caroline Rising <corising@chromium.org>
Reviewed-by: Caroline Rising <corising@chromium.org>
Cr-Commit-Position: refs/heads/master@{#712242}

chrome/browser/ui/views/tabs/tab_hover_card_bubble_view.h

@@ -38,8 +38,6 @@ class TabHoverCardBubbleView : public views::BubbleDialogDelegateView,
   // Updates card content and anchoring and shows the tab hover card.
   void UpdateAndShow(Tab* tab);
 
-  void UpdateAnchorBounds(gfx::Rect anchor_bounds);
-
   bool IsVisible();
 
   void FadeOutToHide();