fix const reference declaration

components/offline_pages/background/request_coordinator.cc

 // Copyright 2016 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/offline_pages/background/request_coordinator.h"
 
 #include <utility>
 
 #include "base/bind.h"
 #include "base/callback.h"
@@ skipping 150 matching lines @@
                           base::Bind(&RequestCoordinator::UpdateRequestCallback,
                                      weak_ptr_factory_.GetWeakPtr()));
 
     // TODO(petewil): Check time budget. Return to the scheduler if we are out.
 
     // Start another request if we have time.
     TryNextRequest();
   }
 }
 
-Scheduler::TriggerConditions const&
+const Scheduler::TriggerConditions&
 RequestCoordinator::GetTriggerConditionsForUserRequest() {
   return kUserRequestTriggerConditions;
 }
 
 void RequestCoordinator::GetOffliner() {
     if (!offliner_) {
       offliner_ = factory_->GetOffliner(policy_.get());
     }
 }
 
 }  // namespace offline_pages