Debug the generic session restore failure.

chrome/browser/sessions/session_service_unittest.cc

 // Copyright (c) 2012 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/bind.h"
 #include "base/bind_helpers.h"
 #include "base/file_util.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/memory/scoped_vector.h"
 #include "base/path_service.h"
+#include "base/run_loop.h"
 #include "base/scoped_temp_dir.h"
 #include "base/stl_util.h"
 #include "base/string_number_conversions.h"
 #include "base/time.h"
 #include "base/utf_string_conversions.h"
 #include "chrome/browser/defaults.h"
 #include "chrome/browser/sessions/session_backend.h"
 #include "chrome/browser/sessions/session_service.h"
 #include "chrome/browser/sessions/session_service_test_helper.h"
 #include "chrome/browser/sessions/session_types.h"
@@ skipping 68 matching lines @@
     entry->SetIsOverridingUserAgent(navigation.is_overriding_user_agent());
     service()->UpdateTabNavigation(window_id, tab_id, index, *entry.get());
     if (select)
       service()->SetSelectedNavigationIndex(window_id, tab_id, index);
   }
 
   void ReadWindows(std::vector<SessionWindow*>* windows) {
     // Forces closing the file.
     helper_.set_service(NULL);
 
+    // SessionBackend posts delayed tasks and might stay alive a bit longer than
+    // SessionService. Make sure the tasks run and the backend is destroyed.
+    base::RunLoop loop;
+    loop.RunUntilIdle();
+
     SessionService* session_service = new SessionService(path_);
     helper_.set_service(session_service);
     helper_.ReadWindows(windows);
   }
 
   // Configures the session service with one window with one tab and a single
   // navigation. If |pinned_state| is true or |write_always| is true, the
   // pinned state of the tab is updated. The session service is then recreated
   // and the pinned state of the read back tab is returned.
   bool CreateAndWriteSessionWithOneTab(bool pinned_state, bool write_always) {
@@ skipping 757 matching lines @@
   ASSERT_TRUE(file_util::CopyFile(v1_file_path, dest_file_path));
 
   SessionService* session_service = new SessionService(path_);
   helper_.set_service(session_service);
   ScopedVector<SessionWindow> windows;
   helper_.ReadWindows(&(windows.get()));
   ASSERT_EQ(1u, windows.size());
   EXPECT_EQ(1u, windows[0]->tabs.size());
 }
 #endif