Adding synthetic field trial for DataReductionProxyEnabled

components/data_reduction_proxy/browser/data_reduction_proxy_settings_test_utils.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/browser/data_reduction_proxy_settings_test_utils.h"
 
+#include "base/bind.h"
 #include "base/command_line.h"
 #include "base/message_loop/message_loop.h"
 #include "base/prefs/pref_registry_simple.h"
 #include "base/prefs/scoped_user_pref_update.h"
 #include "base/strings/string_number_conversions.h"
 #include "components/data_reduction_proxy/common/data_reduction_proxy_pref_names.h"
 #include "components/data_reduction_proxy/common/data_reduction_proxy_switches.h"
 
 using testing::_;
 using testing::AnyNumber;
@@ skipping 275 matching lines @@
                  kWarmupURLWithNoContentResponse,
                  "OK",
                  FetchResult(enabled_at_startup, true),
                  true,
                  enabled_at_startup ? 1 : 0);
   scoped_ptr<DataReductionProxyConfigurator> configurator(
       new TestDataReductionProxyConfig());
   settings_->SetProxyConfigurator(configurator.Pass());
   scoped_refptr<net::TestURLRequestContextGetter> request_context =
       new net::TestURLRequestContextGetter(base::MessageLoopProxy::current());
-  settings_->InitDataReductionProxySettings(&pref_service_,
-                                            &pref_service_,
-                                            request_context.get());
+
+  settings_->InitDataReductionProxySettings(
+      &pref_service_,
+      &pref_service_,
+      request_context.get());
+  settings_->SetOnDataReductionEnabledCallback(
+      base::Bind(&DataReductionProxySettingsTestBase::
+                 RegisterSyntheticFieldTrialCallback,
+                 base::Unretained(this)));
 
   base::MessageLoop::current()->RunUntilIdle();
   CheckProxyConfigs(enabled_at_startup, false, false);
+  EXPECT_EQ(enabled_at_startup, proxy_enabled_);
 }
 
 }  // namespace data_reduction_proxy