Changes instant so that the newly created tab has a new id. Doing

chrome/browser/tabs/tab_strip_model_unittest.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 <map>
 #include <string>
 
 #include "app/system_monitor.h"
 #include "base/file_path.h"
 #include "base/file_util.h"
@@ skipping 323 matching lines @@
                             int index) {
     states_.push_back(new State(contents, index, CLOSE));
   }
   virtual void TabDetachedAt(TabContentsWrapper* contents, int index) {
     states_.push_back(new State(contents, index, DETACH));
   }
   virtual void TabChangedAt(TabContentsWrapper* contents, int index,
                             TabChangeType change_type) {
     states_.push_back(new State(contents, index, CHANGE));
   }
-  virtual void TabReplacedAt(TabContentsWrapper* old_contents,
-                             TabContentsWrapper* new_contents, int index) {
+  virtual void TabReplacedAt(TabStripModel* tab_strip_model,
+                             TabContentsWrapper* old_contents,
+                             TabContentsWrapper* new_contents,
+                             int index) {
     State* s = new State(new_contents, index, REPLACED);
     s ->src_contents = old_contents;
     states_.push_back(s);
   }
   virtual void TabPinnedStateChanged(TabContentsWrapper* contents, int index) {
     states_.push_back(new State(contents, index, PINNED));
   }
   virtual void TabStripEmpty() {
     empty_ = true;
   }
@@ skipping 1534 matching lines @@
   TabStripModel strip(&delegate, profile());
   TabContentsWrapper* contents1 = CreateTabContents();
   TabContentsWrapper* contents2 = CreateTabContents();
   strip.AppendTabContents(contents1, true);
   strip.AppendTabContents(contents2, true);
   // DeleteTabContentsOnDestroyedObserver deletes contents1 when contents2 sends
   // out notification that it is being destroyed.
   DeleteTabContentsOnDestroyedObserver observer(contents2, contents1);
   strip.CloseAllTabs();
 }