Revert "Revert "[mms] Fix regression in retrieving CAPABILITY information after we login.""

This reverts commit 95a9a94f9ffb61357f7286b3362edc64c36b2a8d.
Revert "Pipeline object not needed in this method"

This reverts commit 450ec169e7548374242da0ae8080b4a824d46c9a.
[mms] Fix regression in setting CAPABILITY for IMAP servers that don't automatically send this information after login.