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

chrome/browser/ui/tabs/tab_strip_model_observer.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CHROME_BROWSER_UI_TABS_TAB_STRIP_MODEL_OBSERVER_H_
 #define CHROME_BROWSER_UI_TABS_TAB_STRIP_MODEL_OBSERVER_H_
 
 class TabStripModel;
 
 namespace content {
@@ skipping 53 matching lines @@
   // The specified WebContents at |index| is being closed (and eventually
   // destroyed). |tab_strip_model| is the TabStripModel that contained the tab.
   virtual void TabClosingAt(TabStripModel* tab_strip_model,
                             content::WebContents* contents,
                             int index);
 
   // The specified WebContents at |index| is being detached, perhaps to
   // be inserted in another TabStripModel. The implementer should take whatever
   // action is necessary to deal with the WebContents no longer being
   // present.
-  virtual void TabDetachedAt(content::WebContents* contents, int index);
+  virtual void TabDetachedAt(content::WebContents* contents,
+                             int index,
+                             bool closing_all);

[Avi (use Gerrit), 2013/06/19 14:18:34]

What does "closing_all" mean in this context? This callback is about detachment
of a single tab; "all"?

 
   // The active WebContents is about to change from |old_contents|.
   // This gives observers a chance to prepare for an impending switch before it
   // happens.
   virtual void TabDeactivated(content::WebContents* contents);
 
   // Sent when the active tab changes. The previously active tab is identified
   // by |old_contents| and the newly active tab by |new_contents|. |index| is
   // the index of |new_contents|. If |reason| has CHANGE_REASON_REPLACED set
   // then the web contents was replaced (see TabChangedAt). If |reason| has
@@ skipping 63 matching lines @@
 
   // Sent when the tabstrip model is about to be deleted and any reference held
   // must be dropped.
   virtual void TabStripModelDeleted();
 
  protected:
   virtual ~TabStripModelObserver() {}
 };
 
 #endif  // CHROME_BROWSER_UI_TABS_TAB_STRIP_MODEL_OBSERVER_H_