Removed NOTIFICATION_BROWSER_CLOSING notification

chrome/browser/ui/browser_list_observer.h

Index: chrome/browser/ui/browser_list_observer.h
diff --git a/chrome/browser/ui/browser_list_observer.h b/chrome/browser/ui/browser_list_observer.h
index 42af6d3086e65261be084bbf6d229111a5fb82cf..e514b650d1352fb39089a5d8c067401b92a0898e 100644
--- a/chrome/browser/ui/browser_list_observer.h
+++ b/chrome/browser/ui/browser_list_observer.h
@@ -14,6 +14,10 @@ class BrowserListObserver {
   // Called immediately after a browser is added to the list
   virtual void OnBrowserAdded(Browser* browser) {}
 
+  // Called when a Browser starts closing. This is called prior to
+  // removing the tabs. Removing the tabs may delay or stop the close.
+  virtual void OnBrowserClosing(Browser* browser) {}
+
   // Called immediately after a browser is removed from the list
   virtual void OnBrowserRemoved(Browser* browser) {}