Ensure tests have an active task runner

components/data_reduction_proxy/core/browser/data_reduction_proxy_bypass_protocol_unittest.cc

 // Copyright 2014 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 "components/data_reduction_proxy/core/browser/data_reduction_proxy_bypass_protocol.h"
 
 #include <utility>
 
 #include "base/memory/ref_counted.h"
 #include "base/memory/scoped_ptr.h"
@@ skipping 293 matching lines @@
     if (expected_num_bad_proxies == 2u) {
       ProxyRetryInfoMap::const_iterator i =
           retry_info.find(GetProxyKey(bad_proxy2));
       ASSERT_TRUE(i != retry_info.end());
       EXPECT_TRUE(expected_min_duration <= (*i).second.current_delay);
       EXPECT_TRUE((*i).second.current_delay <= expected_max_duration);
     }
   }
 
  protected:
+  base::MessageLoopForIO message_loop_;
   scoped_ptr<net::NetworkChangeNotifier> network_change_notifier_;
 
   scoped_ptr<net::URLRequestInterceptor> simple_interceptor_;
   net::MockClientSocketFactory mock_socket_factory_;
   scoped_ptr<net::TestNetworkDelegate> network_delegate_;
   scoped_ptr<ProxyService> proxy_service_;
   scoped_ptr<DataReductionProxyTestContext> test_context_;
   scoped_ptr<DataReductionProxyBypassStats> bypass_stats_;
   net::StaticHttpUserAgentSettings http_user_agent_settings_;
 
@@ skipping 539 matching lines @@
   EXPECT_EQ(net::URLRequestStatus::SUCCESS, r->status().status());
   EXPECT_EQ(net::OK, r->status().error());
 
   EXPECT_EQ("Bypass message", d.data_received());
 
   // We should have no entries in our bad proxy list.
   TestBadProxies(0, -1, "", "");
 }
 
 }  // namespace data_reduction_proxy