[Offline Pages] Introducing StorageManagerClient interface.

components/offline_pages/offline_page_model.cc

Index: components/offline_pages/offline_page_model.cc
diff --git a/components/offline_pages/offline_page_model.cc b/components/offline_pages/offline_page_model.cc
index d9a7fa2c689387676369f479fea89ad3d7f88959..3472066eb9fa33f5dfd6b8b1633e85fee0041ffa 100644
--- a/components/offline_pages/offline_page_model.cc
+++ b/components/offline_pages/offline_page_model.cc
@@ -124,7 +124,6 @@ OfflinePageModel::OfflinePageModel(
       is_loaded_(false),
       task_runner_(task_runner),
       policy_controller_(new ClientPolicyController()),
-      storage_manager_(new OfflinePageStorageManager(this)),
       weak_ptr_factory_(this) {
   task_runner_->PostTaskAndReply(
       FROM_HERE, base::Bind(EnsureArchivesDirCreated, archives_dir_),
@@ -637,6 +636,10 @@ void OfflinePageModel::OnLoadDone(
   UMA_HISTOGRAM_TIMES("OfflinePages.Model.ConstructionToLoadedEventTime",
                       base::TimeTicks::Now() - start_time);
 
+  // Create Storage Manager.
+  storage_manager_.reset(
+      new OfflinePageStorageManager(this, GetPolicyController()));
+
   // Run all the delayed tasks.
   for (const auto& delayed_task : delayed_tasks_)
     delayed_task.Run();