Unbreak tabs.onRemove extension API in face of fast tab closure

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 e1db4debf978d18b352b38166752c4c26049ae21..ab29dbf4f304c68f4976ff64d2ab735d8000adf9 100644
--- a/content/browser/web_contents/web_contents_impl.h
+++ b/content/browser/web_contents/web_contents_impl.h
@@ -270,11 +270,13 @@ class CONTENT_EXPORT WebContentsImpl
   virtual void OnCloseStarted() OVERRIDE;
   virtual void OnCloseCanceled() OVERRIDE;
   virtual void OnUnloadStarted() OVERRIDE;
+  virtual void OnUnloadAboutToDetach() OVERRIDE;
   virtual void OnUnloadDetachedStarted() OVERRIDE;
   virtual void SystemDragEnded() OVERRIDE;
   virtual void UserGestureDone() OVERRIDE;
   virtual void SetClosedByUserGesture(bool value) OVERRIDE;
   virtual bool GetClosedByUserGesture() const OVERRIDE;
+  virtual bool GetWebContentsDetachedToClose() const OVERRIDE;
   virtual double GetZoomLevel() const OVERRIDE;
   virtual int GetZoomPercent(bool* enable_increment,
                              bool* enable_decrement) const OVERRIDE;
@@ -882,6 +884,9 @@ class CONTENT_EXPORT WebContentsImpl
   // The time when the tab was removed from view during close.
   base::TimeTicks unload_detached_start_time_;
 
+  // True if the tab was removed from a view during close.
+  bool detached_as_part_of_unload_;
+
   // The time that this tab was last selected.
   base::TimeTicks last_selected_time_;