Add unit test for request coordiator

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"
 
-// TODO(fgorski): include file with SavePageRequest definition.
+#include "components/offline_pages/background/save_page_request.h"
 
 namespace offline_pages {
 
 // TODO(dougarnett): How to inject Offliner factories and policy objects.
 RequestCoordinator::RequestCoordinator() {
   // Do setup as needed.
 }
 
 RequestCoordinator::~RequestCoordinator() {
   // Do cleanup as needed.
 }
 
 bool RequestCoordinator::SavePageLater(const SavePageRequest& request) {
   return true;
 }
 
 bool RequestCoordinator::StartProcessing(
     const ProcessingDoneCallback& callback) {
   return false;
 }
 
 void RequestCoordinator::StopProcessing() {
 }
 
 }  // namespace offline_pages