Pull Up Method	private FileUcDiff(snapshot Snapshot, file INodeFile) from class org.apache.hadoop.hdfs.server.namenode.snapshot.INodeFileUnderConstructionWithSnapshot.FileUcDiff to package FileDiff(snapshot Snapshot, snapshotINode INodeFile, posteriorDiff FileDiff, fileSize long) from class org.apache.hadoop.hdfs.server.namenode.snapshot.FileWithSnapshot.FileDiff