Ensure tests have an active task runner

chrome/browser/sync/startup_controller_unittest.cc

Index: chrome/browser/sync/startup_controller_unittest.cc
diff --git a/chrome/browser/sync/startup_controller_unittest.cc b/chrome/browser/sync/startup_controller_unittest.cc
index 186a7590896101074615d91cc9a5b583212285c8..9c1d53768705e27b24043c9ec61f2e38ea7d33bf 100644
--- a/chrome/browser/sync/startup_controller_unittest.cc
+++ b/chrome/browser/sync/startup_controller_unittest.cc
@@ -16,6 +16,7 @@
 #include "chrome/common/chrome_switches.h"
 #include "chrome/test/base/testing_profile.h"
 #include "components/sync_driver/sync_prefs.h"
+#include "content/public/test/test_browser_thread_bundle.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 namespace browser_sync {
@@ -94,7 +95,7 @@ class StartupControllerTest : public testing::Test {
 
  private:
   bool started_;
-  base::MessageLoop message_loop_;
+  content::TestBrowserThreadBundle thread_bundle_;
   scoped_ptr<StartupController> controller_;
   scoped_ptr<FakeSupervisedUserSigninManagerWrapper> signin_;
   scoped_ptr<FakeProfileOAuth2TokenService> token_service_;