Convert //chrome/browser/sync_file_system from scoped_ptr to std::unique_ptr

chrome/browser/sync_file_system/local/sync_file_system_backend.cc

Index: chrome/browser/sync_file_system/local/sync_file_system_backend.cc
diff --git a/chrome/browser/sync_file_system/local/sync_file_system_backend.cc b/chrome/browser/sync_file_system/local/sync_file_system_backend.cc
index febf9f193be1d67fb598e6a69ad7f769320f4574..d2501511f41ce66f97449bf07e84450b1538855c 100644
--- a/chrome/browser/sync_file_system/local/sync_file_system_backend.cc
+++ b/chrome/browser/sync_file_system/local/sync_file_system_backend.cc
@@ -159,7 +159,7 @@ storage::FileSystemOperation* SyncFileSystemBackend::CreateFileSystemOperation(
   DCHECK(context);
   DCHECK(error_code);
 
-  scoped_ptr<storage::FileSystemOperationContext> operation_context =
+  std::unique_ptr<storage::FileSystemOperationContext> operation_context =
       GetDelegate()->CreateFileSystemOperationContext(url, context, error_code);
   if (!operation_context)
     return nullptr;
@@ -183,7 +183,7 @@ bool SyncFileSystemBackend::HasInplaceCopyImplementation(
   return false;
 }
 
-scoped_ptr<storage::FileStreamReader>
+std::unique_ptr<storage::FileStreamReader>
 SyncFileSystemBackend::CreateFileStreamReader(
     const storage::FileSystemURL& url,
     int64_t offset,
@@ -195,7 +195,7 @@ SyncFileSystemBackend::CreateFileStreamReader(
       url, offset, expected_modification_time, context);
 }
 
-scoped_ptr<storage::FileStreamWriter>
+std::unique_ptr<storage::FileStreamWriter>
 SyncFileSystemBackend::CreateFileStreamWriter(
     const storage::FileSystemURL& url,
     int64_t offset,
@@ -234,7 +234,7 @@ SyncFileSystemBackend* SyncFileSystemBackend::GetBackend(
 }
 
 void SyncFileSystemBackend::SetLocalFileChangeTracker(
-    scoped_ptr<LocalFileChangeTracker> tracker) {
+    std::unique_ptr<LocalFileChangeTracker> tracker) {
   DCHECK(!change_tracker_);
   DCHECK(tracker);
   change_tracker_ = std::move(tracker);