Move datanode heartbeat handling to BlockManager
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Key: HDFS-2108
URL: https://issues.apache.org/jira/browse/HDFS-2108
Project: Hadoop HDFS
Issue Type: Sub-task
Components: name-node
Reporter: Tsz Wo (Nicholas), SZE
Logically, datanodes should heartbeat to block manager instead of name system.
Therefore, we should move datanode heartbeat handling code to {{BlockManager}}.
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