Ensure tests have an active task runner

components/data_reduction_proxy/core/browser/data_reduction_proxy_bypass_stats_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_stats.h"
 
 #include <set>
 #include <string>
 #include <vector>
 
@@ skipping 112 matching lines @@
 
   MockDataReductionProxyConfig* config() const {
     return test_context_->mock_config();
   }
 
   void RunUntilIdle() {
     test_context_->RunUntilIdle();
   }
 
  private:
+  base::MessageLoopForIO message_loop_;
   net::TestURLRequestContext context_;
   net::TestDelegate delegate_;
   scoped_ptr<net::URLRequest> mock_url_request_;
   // |test_job_interceptor_| is owned by |test_job_factory_|.
   net::TestJobInterceptor* test_job_interceptor_;
   net::URLRequestJobFactoryImpl test_job_factory_;
   scoped_ptr<DataReductionProxyTestContext> test_context_;
 };
 
 TEST_F(DataReductionProxyBypassStatsTest, IsDataReductionProxyUnreachable) {
@@ skipping 554 matching lines @@
       const std::string& first_excluded_histogram,
       const std::string& second_excluded_histogram) const {
     std::set<std::string> excluded_histograms;
     excluded_histograms.insert(first_excluded_histogram);
     excluded_histograms.insert(second_excluded_histogram);
     ExpectOtherBypassedBytesHistogramsEmpty(histogram_tester,
                                             excluded_histograms);
   }
 
  private:
+  base::MessageLoopForIO message_loop_;
   net::TestDelegate delegate_;
   net::MockClientSocketFactory mock_socket_factory_;
   net::TestURLRequestContext context_;
   net::URLRequestContextStorage context_storage_;
   scoped_ptr<DataReductionProxyTestContext> drp_test_context_;
 };
 
 TEST_F(DataReductionProxyBypassStatsEndToEndTest, BypassedBytesNoRetry) {
   struct TestCase {
     GURL url;
@@ skipping 213 matching lines @@
   histogram_tester.ExpectUniqueSample(
       "DataReductionProxy.BypassedBytes.NetworkErrorOther", kBody.size(), 1);
   ExpectOtherBypassedBytesHistogramsEmpty(
       histogram_tester, "DataReductionProxy.BypassedBytes.NetworkErrorOther");
   histogram_tester.ExpectUniqueSample(
       "DataReductionProxy.BypassOnNetworkErrorPrimary",
       -net::ERR_PROXY_CONNECTION_FAILED, 1);
 }
 
 }  // namespace data_reduction_proxy