Attempt at fixing crash in tab code. It appears that we end up in a

chrome/browser/tabs/tab_strip_model.cc

 // 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.
 
 #include "chrome/browser/tabs/tab_strip_model.h"
 
 #include <algorithm>
 #include <map>
 
 #include "base/command_line.h"
@@ skipping 123 matching lines @@
   TabContentsData* data = new TabContentsData(contents);
   data->pinned = pin;
   if ((add_types & ADD_INHERIT_GROUP) && selected_contents) {
     if (foreground) {
       // Forget any existing relationships, we don't want to make things too
       // confusing by having multiple groups active at the same time.
       ForgetAllOpeners();
     }
     // Anything opened by a link we deem to have an opener.
     data->SetGroup(&selected_contents->controller());
+    // TODO(sky): nuke when we figure out what is causing 34135.
+    CHECK(data->opener != &(contents->controller()));
   } else if ((add_types & ADD_INHERIT_OPENER) && selected_contents) {
     if (foreground) {
       // Forget any existing relationships, we don't want to make things too
       // confusing by having multiple groups active at the same time.
       ForgetAllOpeners();
     }
     data->opener = &selected_contents->controller();
+    // TODO(sky): nuke when we figure out what is causing 34135.
+    CHECK(data->opener != &(contents->controller()));
   }
 
   contents_data_.insert(contents_data_.begin() + index, data);
 
   if (index <= selected_index_) {
     // If a tab is inserted before the current selected index,
     // then |selected_index| needs to be incremented.
     ++selected_index_;
   }
 
   FOR_EACH_OBSERVER(TabStripModelObserver, observers_,
       TabInsertedAt(contents, index, foreground));
 
   if (foreground)
     ChangeSelectedContentsFrom(selected_contents, index, false);
 }
 
 TabContentsWrapper* TabStripModel::ReplaceTabContentsAt(
     int index,
     TabContentsWrapper* new_contents) {
-  // TODO: this should reset group/opener of any tabs that point at
-  // old_contents.
   DCHECK(ContainsIndex(index));
   TabContentsWrapper* old_contents = GetContentsAt(index);
 
+  ForgetOpenersAndGroupsReferencing(&(old_contents->controller()));
+
   contents_data_[index]->contents = new_contents;
 
   FOR_EACH_OBSERVER(TabStripModelObserver, observers_,
                     TabReplacedAt(this, old_contents, new_contents, index));
 
   // When the selected tab contents is replaced send out selected notification
   // too. We do this as nearly all observers need to treat a replace of the
   // selected contents as selection changing.
   if (selected_index_ == index) {
     FOR_EACH_OBSERVER(TabStripModelObserver, observers_,
@@ skipping 24 matching lines @@
 
   TabContentsWrapper* removed_contents = GetContentsAt(index);
   // TODO(sky): nuke reason and old_data when we figure out what is causing
   // 34135.
   volatile int reason = 0;
   int next_selected_index =
       order_controller_->DetermineNewSelectedIndex(index, &reason);
   volatile TabContentsData old_data = *contents_data_.at(index);
   delete contents_data_.at(index);
   contents_data_.erase(contents_data_.begin() + index);
+  ForgetOpenersAndGroupsReferencing(&(removed_contents->controller()));
   if (empty())
     closing_all_ = true;
   FOR_EACH_OBSERVER(TabStripModelObserver, observers_,
       TabDetachedAt(removed_contents, index));
   if (empty()) {
     // TabDetachedAt() might unregister observers, so send |TabStripEmtpy()| in
     // a second pass.
     FOR_EACH_OBSERVER(TabStripModelObserver, observers_, TabStripEmpty());
   } else {
     if (index == selected_index_) {
@@ skipping 779 matching lines @@
   FOR_EACH_OBSERVER(TabStripModelObserver, observers_,
                     TabMoved(moved_data->contents, index, to_position));
 }
 
 // static
 bool TabStripModel::OpenerMatches(const TabContentsData* data,
                                   const NavigationController* opener,
                                   bool use_group) {
   return data->opener == opener || (use_group && data->group == opener);
 }
+
+void TabStripModel::ForgetOpenersAndGroupsReferencing(
+    const NavigationController* tab) {
+  for (TabContentsDataVector::const_iterator i = contents_data_.begin();
+       i != contents_data_.end(); ++i) {
+    if ((*i)->group == tab)
+      (*i)->group = NULL;
+    if ((*i)->opener == tab)
+      (*i)->opener = NULL;
+  }
+}