Drive: remove costly and unnecessary call to getLockInfo in FileSystemItem adaptation when calling GetChildren / ScrollDescendants

Release Notes

Adaptation of a document as a FileSystemItem for the Nuxeo Drive synchronization has been optimized by not fecthing the lock information when unnecessary, typically in the case of a call to the NuxeoDrive.GetChildren or NuxeoDrive.ScrollDescendants operation.

Technical Details

JVM sampling during a call to GetChildren shows that DefaultFileSystemItemFactory#adaptDocument spends a lot of time in DocumentModelImpl#getLockInfo.
Attached visualvm snapshot shows that on a call with 1.000 children approximatively 1000 ms come from getLockInfo.

Currently there is 1 occurrence of getLockInfo in AbstractDocumentBackedFileSystemItem:

    protected AbstractDocumentBackedFileSystemItem(String factoryName, FolderItem parentItem, DocumentModel doc,
            boolean relaxSyncRootConstraint) {
        ...
        lockInfo = doc.getLockInfo();
    }

In the case of a call to DocumentBackedFolderItem#getChildren or DocumentBackedFolderItem#getDescendants we can probably skip this call.

Indeed, this flag is only used by Drive in Processor._synchronize_locally_modified where the remote info (FileSystemItem) is re-fetched to have a fresh state, so storing it for the initial pair state is not required.

This is the same kind of issue as NXP-19441.