Use SNAPSHOT sync mode for LocalSync

chrome/browser/sync_file_system/syncable_file_system_util.h

Index: chrome/browser/sync_file_system/syncable_file_system_util.h
diff --git a/chrome/browser/sync_file_system/syncable_file_system_util.h b/chrome/browser/sync_file_system/syncable_file_system_util.h
index 408f72c553828b5555062114ca49d8720a2d6522..3cce3ad1f1a79f1de381d53899b2e6f28a89d2a2 100644
--- a/chrome/browser/sync_file_system/syncable_file_system_util.h
+++ b/chrome/browser/sync_file_system/syncable_file_system_util.h
@@ -85,6 +85,9 @@ void SetEnableSyncFSDirectoryOperation(bool flag);
 // away when we fully support directory operations. (http://crbug.com/161442)
 bool IsSyncFSDirectoryOperationEnabled();
 
+// Returns SyncFileSystem sub-directory path.
+base::FilePath GetSyncFileSystemDir(const base::FilePath& profile_base_dir);
+
 // Enables directory operation for syncable filesystems temporarily for testing.
 class ScopedEnableSyncFSDirectoryOperation {
  public: