Fix duplicate logging of ActiveBrowserChanged action on views.

chrome/browser/metrics/desktop_session_duration/chrome_visibility_observer.h

Index: chrome/browser/metrics/desktop_session_duration/chrome_visibility_observer.h
diff --git a/chrome/browser/metrics/desktop_session_duration/chrome_visibility_observer.h b/chrome/browser/metrics/desktop_session_duration/chrome_visibility_observer.h
index 3122503228513733ac01f1607dc47232b132e0ba..7740391d4d43da57a1ec31ae0f1b8b4d38c177ab 100644
--- a/chrome/browser/metrics/desktop_session_duration/chrome_visibility_observer.h
+++ b/chrome/browser/metrics/desktop_session_duration/chrome_visibility_observer.h
@@ -21,10 +21,6 @@ class ChromeVisibilityObserver : public chrome::BrowserListObserver {
   // by tests.
   virtual void SendVisibilityChangeEvent(bool active, base::TimeDelta time_ago);
 
-  // chrome::BrowserListObserver:
-  // In protected section for test.
-  void OnBrowserRemoved(Browser* browser) override;
-
  private:
   // Cancels visibility change in case when the browser becomes visible after a
   // short gap.
@@ -33,6 +29,7 @@ class ChromeVisibilityObserver : public chrome::BrowserListObserver {
   // chrome::BrowserListObserver:
   void OnBrowserSetLastActive(Browser* browser) override;
   void OnBrowserNoLongerActive(Browser* browser) override;
+  void OnBrowserRemoved(Browser* browser) override;
 
   // Sets |visibility_gap_timeout_| based on variation params.
   void InitVisibilityGapTimeout();