SERVER-42689 M/R Agg: Implement/Test Upgrade and Downgrade behavior

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• Closed

SERVER-42748 M/R Agg: Support using stored procedures (system.js) in map/reduce arguments

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• Closed

SERVER-42916 M/R Agg: Reject non-inline mapReduce to an existing sharded collection that is not sharded by _id

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• Closed

SERVER-43414 M/R Agg: Add deprecation warning for out.sharded in new implementation

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• Closed

SERVER-43578 M/R Agg: Reject mapreduce command sent to mongos with output mode "replace" and sharded: true

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• Closed

SERVER-43625 MR Agg: Implement tests for sharded mapReduce's which are eligible for exchange

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• Closed

SERVER-43626 MR Agg: Fail and cleanup cursors when a sharded mapReduce cannot fit in a single batch response

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• Closed

SERVER-43628 Consolidate cluster aggregation targeting for passthrough/single shard queries

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• Closed

SERVER-43844 Remove unnecessary collation object on agg ExpressionContext

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• Closed