Adds some debugging code in hopes of figuring out why we're

chrome/browser/tabs/tab_strip_model_order_controller.h

 // Copyright (c) 2010 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_TABS_TAB_STRIP_MODEL_ORDER_CONTROLLER_H_
 #define CHROME_BROWSER_TABS_TAB_STRIP_MODEL_ORDER_CONTROLLER_H_
 #pragma once
 
 #include "chrome/browser/tabs/tab_strip_model.h"
 #include "chrome/common/page_transition_types.h"
@@ skipping 22 matching lines @@
   // Determine where to place a newly opened tab by using the supplied
   // transition and foreground flag to figure out how it was opened.
   int DetermineInsertionIndex(TabContentsWrapper* new_contents,
                               PageTransition::Type transition,
                               bool foreground);
 
   // Returns the index to append tabs at.
   int DetermineInsertionIndexForAppending();
 
   // Determine where to shift selection after a tab is closed.
-  int DetermineNewSelectedIndex(int removed_index) const;
+  // TODO(sky): nuke reason when we figure out what is causing 34135.
+  int DetermineNewSelectedIndex(int removed_index, volatile int* reason) const;
 
   // Overridden from TabStripModelObserver:
   virtual void TabSelectedAt(TabContentsWrapper* old_contents,
                              TabContentsWrapper* new_contents,
                              int index,
                              bool user_gesture);
 
  private:
   // Returns a valid index to be selected after the tab at |removing_index| is
   // closed. If |index| is after |removing_index|, |index| is adjusted to
   // reflect the fact that |removing_index| is going away.
   int GetValidIndex(int index, int removing_index) const;
 
   TabStripModel* tabstrip_;
 
   TabStripModel::InsertionPolicy insertion_policy_;
 
   DISALLOW_COPY_AND_ASSIGN(TabStripModelOrderController);
 };
 
 #endif  // CHROME_BROWSER_TABS_TAB_STRIP_MODEL_ORDER_CONTROLLER_H_