Rename Variable	pendingCacheList : List<Block> to pendingCacheCommand : DatanodeCommand in method public handleHeartbeat(nodeReg DatanodeRegistration, blockPoolId String, capacity long, dfsUsed long, remaining long, blockPoolUsed long, cacheCapacity long, cacheUsed long, xceiverCount int, maxTransfers int, failedVolumes int) : DatanodeCommand[] in class org.apache.hadoop.hdfs.server.blockmanagement.DatanodeManager