Deleting messages with large attachments takes a long time over a slower Internet connection.  The operation completes successfully, but it appears that the entire attachment is downloaded before the message is deleted. 

Reproducible: Always

Steps to Reproduce:
1. Delete messages with large attachments over slow connection
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Actual Results:  
Messages are deleted correctly, but only after waiting for what appears to be the message plus attachments to download. 

Expected Results:  
Messages are deleted without downloading entire message with attachments first.