Hook up the SequencedWorkerPool to the browser thread.

chrome/browser/visitedlink/visitedlink_unittest.cc

 // Copyright (c) 2011 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 <cstdio>
 #include <string>
 #include <vector>
 
 #include "base/file_util.h"
 #include "base/message_loop.h"
@@ skipping 98 matching lines @@
       history_service_->SetOnBackendDestroyTask(MessageLoop::QuitClosure());
       history_service_->Cleanup();
       history_service_ = NULL;
 
       // Wait for the backend class to terminate before deleting the files and
       // moving to the next test. Note: if this never terminates, somebody is
       // probably leaking a reference to the history backend, so it never calls
       // our destroy task.
       MessageLoop::current()->Run();
     }
+
+    // Wait for all pending file I/O to be completed.
+    BrowserThread::GetBlockingPool()->FlushForTesting();
   }
 
   // Loads the database from disk and makes sure that the same URLs are present
   // as were generated by TestIO_Create(). This also checks the URLs with a
   // slave to make sure it reads the data properly.
   void Reload() {
     // Clean up after our caller, who may have left the database open.
     ClearDB();
 
     ASSERT_TRUE(InitHistory());
@@ skipping 591 matching lines @@
   EXPECT_EQ(1, profile()->add_event_count());
   EXPECT_EQ(0, profile()->reset_event_count());
 
   // Activate the tab.
   rvh()->WasRestored();
 
   // We should have only one more reset event.
   EXPECT_EQ(1, profile()->add_event_count());
   EXPECT_EQ(1, profile()->reset_event_count());
 }