Supervised user interstitial: Don't destroy WebContents that might still be in use

chrome/browser/supervised_user/supervised_user_browsertest.cc

 // Copyright 2014 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 "base/command_line.h"
 #include "base/prefs/pref_service.h"
 #include "base/strings/utf_string_conversions.h"
 #include "base/values.h"
 #include "chrome/browser/chrome_notification_types.h"
 #include "chrome/browser/history/history_service_factory.h"
@@ skipping 196 matching lines @@
       browser(), test_url, NEW_FOREGROUND_TAB,
       ui_test_utils::BROWSER_TEST_WAIT_FOR_NAVIGATION);
 
   // Check that we got the interstitial.
   WebContents* tab = tab_strip->GetActiveWebContents();
   CheckShownPageIsInterstitial(tab);
 
   // On pressing the "back" button, the new tab should be closed, and we should
   // get back to the previous active tab.
   MockTabStripModelObserver observer(tab_strip);
+  base::RunLoop run_loop;
   EXPECT_CALL(observer,
-              TabClosingAt(tab_strip, tab, tab_strip->active_index()));
+              TabClosingAt(tab_strip, tab, tab_strip->active_index()))
+      .WillOnce(testing::InvokeWithoutArgs(&run_loop, &base::RunLoop::Quit));
   GoBack(tab);
+  run_loop.Run();
   EXPECT_EQ(prev_tab, tab_strip->GetActiveWebContents());
 }
 
 // Tests whether a visit attempt adds a special history entry.
 IN_PROC_BROWSER_TEST_F(SupervisedUserBlockModeTest,
                        HistoryVisitRecorded) {
   GURL allowed_url("http://www.example.com/files/simple.html");
 
   // Set the host as allowed.
   scoped_ptr<base::DictionaryValue> dict(new base::DictionaryValue);
@@ skipping 73 matching lines @@
       dict.PassAs<base::Value>());
   EXPECT_EQ(
       SupervisedUserService::MANUAL_ALLOW,
       supervised_user_service_->GetManualBehaviorForHost(test_url.host()));
 
   observer.Wait();
   EXPECT_EQ(test_url, web_contents->GetURL());
 }
 
 }  // namespace