goxdcr stats values not correct

ns_server stats integration is done, and goxdcr stats are showing up on UI. However, the values shown are not correct, because the values goxdcr tracks are not correct.

After running pipeline that replicates 10000 docs, following is the stats printed in goxdcr log. A few stats is correct, e.g., docs_received_from_dcp. Most stats are not correct, e.g., changes_left, data_replicated, etc.

Stats for pipeline replicationSpec/eac28c9eef6090df44d84b4c8a5f789d/default/target-930247005 {"CkptMgr": {"num_checkpoints": 0, "num_failedckpts": 0, "time_committing": {"count": 0, "max": 0, "mean": 0, "min": 0}}, "Errors": "[]", "Overview":

{"bandwidth_usage": 0, "changes_left": 100000, "data_replicated": 0, "docs_checked": 0, "docs_filtered": 0, "docs_opt_repd": 0, "docs_received_from_dcp": 100000, "docs_rep_queue": 328, "docs_written": 0, "num_checkpoints": 0, "num_failedckpts": 0, "rate_doc_checks": 0, "rate_doc_opt_repd": 0, "rate_replicated": 0, "size_rep_queue": 349219, "time_committing": 0, "wtavg_docs_latency": 0, "wtavg_meta_latency": 2.503}

, "Progress": "Pipeline is running", "Status": "Replicating", "XDCRRouter":

{"docs_filtered": 0}

, "dcp_replicationSpec/eac28c9eef6090df44d84b4c8a5f789d/default/target_127.0.0.1:12000_0":

{"docs_received_from_dcp": 50000}

, "dcp_replicationSpec/eac28c9eef6090df44d84b4c8a5f789d/default/target_127.0.0.1:12000_1":

{"docs_received_from_dcp": 50000}

, "xmem_replicationSpec/eac28c9eef6090df44d84b4c8a5f789d/default/target_127.0.0.1:12000_0": {"data_replicated": 0, "docs_opt_repd": 0, "docs_rep_queue":

{"count": 50000, "max": 1536, "mean": 328.139, "min": 20}

, "docs_written": 0, "size_rep_queue": {"count": 50000, "max": 1620270, "mean": 349219.017, "min": 21180}}, "xmem_replicationSpec/eac28c9eef6090df44d84b4c8a5f789d/default/target_127.0.0.1:12000_1": {"data_replicated": 0, "docs_opt_repd": 0, "docs_rep_queue":

{"count": 50000, "max": 1382, "mean": 531.626, "min": 17}

, "docs_written": 0, "size_rep_queue":

{"count": 50000, "max": 1466715, "mean": 549873.468, "min": 18003}

}}