Remove WebContents::Was{Hidden,Shown}() from the content public interface

content/browser/web_contents/web_contents_impl.h

Index: content/browser/web_contents/web_contents_impl.h
diff --git a/content/browser/web_contents/web_contents_impl.h b/content/browser/web_contents/web_contents_impl.h
index 266e3efb32e2fc62b34474e823879cbdce6ec4c9..5eefc9fd7c35ef69e7869766de826313b1d5c87b 100644
--- a/content/browser/web_contents/web_contents_impl.h
+++ b/content/browser/web_contents/web_contents_impl.h
@@ -203,6 +203,10 @@ class CONTENT_EXPORT WebContentsImpl
 
   bool should_normally_be_visible() { return should_normally_be_visible_; }
 
+  // Invoked when the WebContentsView becomes visible to the user, or is hidden.
+  void WasShown();
+  void WasHidden();
+
   // Indicate if the window has been occluded, and pass this to the views, only
   // if there is no active capture going on (otherwise it is dropped on the
   // floor).
@@ -293,8 +297,7 @@ class CONTENT_EXPORT WebContentsImpl
   void NotifyNavigationStateChanged(InvalidateTypes changed_flags) override;
   base::TimeTicks GetLastActiveTime() const override;
   void SetLastActiveTime(base::TimeTicks last_active_time) override;
-  void WasShown() override;
-  void WasHidden() override;
+  void MarkBackgrounded() override;
   bool NeedToFireBeforeUnload() override;
   void DispatchBeforeUnload(bool for_cross_site_transition) override;
   void AttachToOuterWebContentsFrame(