Fix tab deselect notifications.

ios/chrome/browser/tabs/tab_model_selected_tab_observer.mm

 // Copyright 2017 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.
 
 #import "ios/chrome/browser/tabs/tab_model_selected_tab_observer.h"
 
 #include "base/logging.h"
 #import "ios/chrome/browser/tabs/legacy_tab_helper.h"
 #import "ios/chrome/browser/tabs/tab.h"
 #import "ios/chrome/browser/tabs/tab_model.h"
@@ skipping 27 matching lines @@
     // Save state, such as scroll position, ... of the old selected Tab.
     oldTab = LegacyTabHelper::GetTabForWebState(oldWebState);
     if (userAction)
       [oldTab recordStateInHistory];
 
     // Avoid artificially extending the lifetime of oldTab until the global
     // autoreleasepool is purged.
     @autoreleasepool {
       [[NSNotificationCenter defaultCenter]
           postNotificationName:kTabModelTabDeselectedNotification
-                        object:@{kTabModelTabKey : oldTab}];
+                        object:_tabModel
+                      userInfo:@{kTabModelTabKey : oldTab}];
     }
   }
 
   if (newWebState) {
     newTab = LegacyTabHelper::GetTabForWebState(newWebState);
     [newTab updateLastVisitedTimestamp];
 
     // Persist the session state.
     if (newTab.loadFinished)
       [_tabModel saveSessionImmediately:NO];
   }
 }
 
 @end