Ensure tests have an active task runner

components/data_reduction_proxy/core/browser/data_reduction_proxy_config_unittest.cc

 // Copyright 2015 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_config.h"
 
 #include "base/command_line.h"
 #include "base/strings/string_util.h"
 #include "components/data_reduction_proxy/core/browser/data_reduction_proxy_config_test_utils.h"
 #include "components/data_reduction_proxy/core/browser/data_reduction_proxy_configurator_test_utils.h"
@@ skipping 161 matching lines @@
 
   TestDataReductionProxyConfigurator* configurator() {
     return test_context_->test_configurator();
   }
 
   TestDataReductionProxyParams* params() const {
     return expected_params_.get();
   }
 
  private:
+  base::MessageLoopForIO message_loop_;
   scoped_ptr<DataReductionProxyTestContext> test_context_;
   scoped_ptr<TestDataReductionProxyParams> expected_params_;
 };
 
 TEST_F(DataReductionProxyConfigTest, TestUpdateConfigurator) {
   base::CommandLine::ForCurrentProcess()->AppendSwitchASCII(
       switches::kDataReductionProxyAlt, params()->DefaultAltOrigin());
   base::CommandLine::ForCurrentProcess()->AppendSwitchASCII(
       switches::kDataReductionProxyAltFallback,
       params()->DefaultAltFallbackOrigin());
@@ skipping 566 matching lines @@
   base::TimeDelta min_retry_delay;
   was_bypassed = config->AreProxiesBypassed(retry_map,
                                             rules,
                                             false,
                                             &min_retry_delay);
   EXPECT_TRUE(was_bypassed);
   EXPECT_EQ(delay, min_retry_delay);
 }
 
 }  // namespace data_reduction_proxy