Have content/ create and destroy its own threads.

chrome/browser/internal_auth_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 "chrome/browser/internal_auth.h"
 
 #include <algorithm>
 
 #include "base/lazy_instance.h"
+#include "base/message_loop.h"
 #include "base/time.h"
 #include "content/test/test_browser_thread.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 namespace browser {
 
 class InternalAuthTest : public ::testing::Test {
  public:
   InternalAuthTest() {
     long_string_ = "seed";
@@ skipping 170 matching lines @@
   token = browser::InternalAuthGeneration::GeneratePassport("zapata", map);
   ASSERT_GT(token.size(), 10u);
   for (int i = 20; i--;)
     browser::InternalAuthGeneration::GenerateNewKey();
   // Passport should not survive series of key changes.
   ASSERT_FALSE(browser::InternalAuthVerification::VerifyPassport(
       token, "zapata", map));
 }
 
 }  // namespace browser