OAK-1374: Async indexer fails on the SegmentMK

The property record could be on a different segment than the blob value,
so avoid throwing away the segment identifier included in the RecordId.
The SegmentBlob instance will automatically resolve the correct segment.

git-svn-id: https://svn.apache.org/repos/asf/jackrabbit/oak/trunk@1564333 13f79535-47bb-0310-9956-ffa450edef68