Ensure tests have an active task runner

chrome/browser/net/dns_probe_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 "chrome/browser/net/dns_probe_service.h"
 
 #include "base/bind.h"
 #include "base/compiler_specific.h"
 #include "base/memory/weak_ptr.h"
 #include "base/message_loop/message_loop.h"
@@ skipping 56 matching lines @@
     service_.ClearCachedResultForTesting();
   }
 
  private:
   void ProbeCallback(DnsProbeStatus result) {
     EXPECT_FALSE(callback_called_);
     callback_called_ = true;
     callback_result_ = result;
   }
 
+  TestBrowserThreadBundle bundle_;
   DnsProbeService service_;
   bool callback_called_;
   DnsProbeStatus callback_result_;
-  TestBrowserThreadBundle bundle_;
 };
 
 TEST_F(DnsProbeServiceTest, Probe_OK_OK) {
   RunTest(MockDnsClientRule::OK, MockDnsClientRule::OK,
           chrome_common_net::DNS_PROBE_FINISHED_NXDOMAIN);
 }
 
 TEST_F(DnsProbeServiceTest, Probe_TIMEOUT_OK) {
   RunTest(MockDnsClientRule::TIMEOUT, MockDnsClientRule::OK,
           chrome_common_net::DNS_PROBE_FINISHED_BAD_CONFIG);
@@ skipping 33 matching lines @@
   // Pretend cache expires.
   ClearCachedResult();
   // New rules should apply, since a new probe should be run.
   RunTest(MockDnsClientRule::TIMEOUT, MockDnsClientRule::TIMEOUT,
           chrome_common_net::DNS_PROBE_FINISHED_NO_INTERNET);
 }
 
 }  // namespace
 
 }  // namespace chrome_browser_net