IOperation.Elapsed does not correctly count duration between retries

What's happening

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A special clause:

if (operation.Elapsed < operation.Timeout && !operation.IsCompleted) throw;

is being hit with for KV operations when unsuccesful sometimes.

Problem

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The stopwatch field of IOperation/OperationBase is stopped early in HandleOperationCompleted(), called from AsyncStateBase.cs : SendResponseInternal().
 

Affected

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All KV operations

This issue can be re-created consistently with

• The "Test expected behaviour when a collection is dropped" Test in the RangeScan FIT Driver suite. A TaskCanceledException is thrown.
• Creating a collection, connecting to it with CollectionAsync(), deleting that connection, then attempting to perform a KV op on that collection.