[NOCOMMIT] Make DriveService{Wrapper|Messenger} class

chrome/browser/sync_file_system/drive_backend/sync_engine_context.cc

Index: chrome/browser/sync_file_system/drive_backend/sync_engine_context.cc
diff --git a/chrome/browser/sync_file_system/drive_backend/sync_engine_context.cc b/chrome/browser/sync_file_system/drive_backend/sync_engine_context.cc
index b8cadb9fc0441db7a4cc0ed6fdf1f93406c753ab..0f2c153234048f0d737560c56a21e4d35968674f 100644
--- a/chrome/browser/sync_file_system/drive_backend/sync_engine_context.cc
+++ b/chrome/browser/sync_file_system/drive_backend/sync_engine_context.cc
@@ -17,11 +17,11 @@ namespace sync_file_system {
 namespace drive_backend {
 
 SyncEngineContext::SyncEngineContext(
-    drive::DriveServiceInterface* drive_service,
+    scoped_ptr<drive::DriveServiceInterface> drive_service,
     drive::DriveUploaderInterface* drive_uploader,
     base::SequencedTaskRunner* ui_task_runner,
     base::SequencedTaskRunner* file_task_runner)
-    : drive_service_(drive_service),
+    : drive_service_(drive_service.Pass()),
       drive_uploader_(drive_uploader),
       remote_change_processor_(NULL),
       ui_task_runner_(ui_task_runner),
@@ -30,7 +30,7 @@ SyncEngineContext::SyncEngineContext(
 SyncEngineContext::~SyncEngineContext() {}
 
 drive::DriveServiceInterface* SyncEngineContext::GetDriveService() {
-  return drive_service_;
+  return drive_service_.get();
 }
 
 drive::DriveUploaderInterface* SyncEngineContext::GetDriveUploader() {