[NOCOMMIT] Make DriveService{Wrapper|Messenger} class

chrome/browser/sync_file_system/drive_backend/sync_engine.cc

Index: chrome/browser/sync_file_system/drive_backend/sync_engine.cc
diff --git a/chrome/browser/sync_file_system/drive_backend/sync_engine.cc b/chrome/browser/sync_file_system/drive_backend/sync_engine.cc
index e313787a69ccf90eae465d62bd4c6f3c9a3edcc3..9edaa77d8454cdf95ec44429d7d91dbd4e7de36a 100644
--- a/chrome/browser/sync_file_system/drive_backend/sync_engine.cc
+++ b/chrome/browser/sync_file_system/drive_backend/sync_engine.cc
@@ -7,6 +7,7 @@
 #include <vector>
 
 #include "base/bind.h"
+#include "base/memory/weak_ptr.h"
 #include "base/threading/sequenced_worker_pool.h"
 #include "base/values.h"
 #include "chrome/browser/drive/drive_api_service.h"
@@ -20,6 +21,8 @@
 #include "chrome/browser/signin/signin_manager_factory.h"
 #include "chrome/browser/sync_file_system/drive_backend/conflict_resolver.h"
 #include "chrome/browser/sync_file_system/drive_backend/drive_backend_constants.h"
+#include "chrome/browser/sync_file_system/drive_backend/drive_service_messenger.h"
+#include "chrome/browser/sync_file_system/drive_backend/drive_service_wrapper.h"
 #include "chrome/browser/sync_file_system/drive_backend/list_changes_task.h"
 #include "chrome/browser/sync_file_system/drive_backend/local_to_remote_syncer.h"
 #include "chrome/browser/sync_file_system/drive_backend/metadata_database.h"
@@ -90,11 +93,6 @@ scoped_ptr<SyncEngine> SyncEngine::CreateForBrowserContext(
   ExtensionService* extension_service =
       extensions::ExtensionSystem::Get(context)->extension_service();
 
-  scoped_refptr<base::SequencedTaskRunner> file_task_runner(
-      worker_pool->GetSequencedTaskRunnerWithShutdownBehavior(
-          worker_pool->GetSequenceToken(),
-          base::SequencedWorkerPool::SKIP_ON_SHUTDOWN));
-
   // TODO(peria): Create another task runner to manage SyncWorker.
   scoped_refptr<base::SingleThreadTaskRunner>
       worker_task_runner = base::MessageLoopProxy::current();
@@ -106,10 +104,17 @@ scoped_ptr<SyncEngine> SyncEngine::CreateForBrowserContext(
                      notification_manager,
                      extension_service,
                      signin_manager));
+
+  scoped_refptr<base::SequencedTaskRunner> file_task_runner(
+      worker_pool->GetSequencedTaskRunnerWithShutdownBehavior(
+          worker_pool->GetSequenceToken(),
+          base::SequencedWorkerPool::SKIP_ON_SHUTDOWN));
+
   sync_engine->Initialize(
       GetSyncFileSystemDir(context->GetPath()),
       file_task_runner.get(),
-      NULL);
+      false,
+      NULL /* env_override */);
 
   return sync_engine.Pass();
 }
@@ -132,12 +137,24 @@ SyncEngine::~SyncEngine() {
 
 void SyncEngine::Initialize(const base::FilePath& base_dir,

[peria, 2014/04/24 04:08:38]

It may be good to make InitializeForTesting().
In product code, |pass_service_to_worker| must be false and |env_override| must
be NULL.
And we are planning to remove |pass_service_to_worker| argument in the near
future.

                             base::SequencedTaskRunner* file_task_runner,
+                            bool pass_service_to_worker,
                             leveldb::Env* env_override) {
-  scoped_ptr<SyncEngineContext> sync_engine_context(
-      new SyncEngineContext(drive_service_.get(),
-                            drive_uploader_.get(),
-                            base::MessageLoopProxy::current(),
-                            file_task_runner));
+  scoped_ptr<SyncEngineContext> sync_engine_context;
+  if (pass_service_to_worker) {
+    sync_engine_context.reset(
+        new SyncEngineContext(drive_service_.Pass(),
+                              drive_uploader_.get(),
+                              base::MessageLoopProxy::current(),
+                              file_task_runner));
+  } else {
+    scoped_ptr<drive::DriveServiceInterface> drive_service_messenger(
+        new DriveServiceMessenger(drive_service_wrapper_->AsWeakPtr()));
+    sync_engine_context.reset(
+        new SyncEngineContext(drive_service_messenger.Pass(),
+                              drive_uploader_.get(),
+                              base::MessageLoopProxy::current(),
+                              file_task_runner));
+  }
   // TODO(peria): Use PostTask on |worker_task_runner_| to call this function.
   sync_worker_ = SyncWorker::CreateOnWorker(weak_ptr_factory_.GetWeakPtr(),
                                             base_dir,
@@ -366,11 +383,11 @@ void SyncEngine::OnNetworkChanged(
 }
 
 drive::DriveServiceInterface* SyncEngine::GetDriveService() {
-  return drive_service_.get();
+  return sync_worker_->GetDriveService();
 }
 
 drive::DriveUploaderInterface* SyncEngine::GetDriveUploader() {
-  return drive_uploader_.get();
+  return sync_worker_->GetDriveUploader();
 }
 
 MetadataDatabase* SyncEngine::GetMetadataDatabase() {
@@ -386,6 +403,7 @@ SyncEngine::SyncEngine(
     ExtensionServiceInterface* extension_service,
     SigninManagerBase* signin_manager)
     : drive_service_(drive_service.Pass()),
+      drive_service_wrapper_(new DriveServiceWrapper(drive_service_.get())),
       drive_uploader_(drive_uploader.Pass()),
       notification_manager_(notification_manager),
       extension_service_(extension_service),