Move all components/offline_pages/ files into component/offline_pages/core

components/offline_pages/background/mark_attempt_started_task.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/mark_attempt_started_task.h"
-
-#include <utility>
-
-#include "base/bind.h"
-#include "base/time/time.h"
-
-namespace offline_pages {
-
-MarkAttemptStartedTask::MarkAttemptStartedTask(
-    RequestQueueStore* store,
-    int64_t request_id,
-    const RequestQueueStore::UpdateCallback& callback)
-    : UpdateRequestTask(store, request_id, callback) {}
-
-MarkAttemptStartedTask::~MarkAttemptStartedTask() {}
-
-void MarkAttemptStartedTask::UpdateRequestImpl(
-    std::unique_ptr<UpdateRequestsResult> read_result) {
-  if (!ValidateReadResult(read_result.get())) {
-    CompleteWithResult(std::move(read_result));
-    return;
-  }
-
-  // It is perfectly fine to reuse the read_result->updated_items collection, as
-  // it is owned by this callback and will be destroyed when out of scope.
-  read_result->updated_items[0].MarkAttemptStarted(base::Time::Now());
-  store()->UpdateRequests(
-      read_result->updated_items,
-      base::Bind(&MarkAttemptStartedTask::CompleteWithResult, GetWeakPtr()));
-}
-
-}  // namespace offline_pages