Revert "MB-9715: Fixup UPR step"

This reverts commit cac72f4cd6abff127364c9251d42bb5a45a71c68.

Change-Id: Ifcb9ca1da7699787bc18ec79a61895030c61f5b8
Reviewed-on: http://review.couchbase.org/31429
Reviewed-by: Michael Wiederhold <mike@couchbase.com>
Tested-by: Michael Wiederhold <mike@couchbase.com>
Use dirutils from platform/

Change-Id: I271c8dde19ce76d61b13f55f302d8d2e753a2446
Reviewed-on: http://review.couchbase.org/31418
Reviewed-by: Michael Wiederhold <mike@couchbase.com>
Tested-by: Trond Norbye <trond.norbye@gmail.com>
Fixup error message for failed to remove file

Change-Id: I2a9d355ee53b4a70c3ef240ba4e39a4475350a31
Reviewed-on: http://review.couchbase.org/31422
Reviewed-by: Trond Norbye <trond.norbye@gmail.com>
Tested-by: Trond Norbye <trond.norbye@gmail.com>
MB-9741 Replace usage of QueuedItem with Item class.

This is the first phase of reducing memory used by keys/metadata of items.
This checkin now replace QueuedItem with Item used by Checkpoing Manager
and prepares for using Item class in StoredValue. QueuedItem is removed
from the code base.

Change-Id: I6afecac51410f209155cf357f6a276c20670b026
Reviewed-on: http://review.couchbase.org/31050
Reviewed-by: Michael Wiederhold <mike@couchbase.com>
Tested-by: Michael Wiederhold <mike@couchbase.com>
Add a snapshot marker when backfill ends

Backfilling items from disk is considered a snapshot so we need
to make sure that we add a snapshot marker to the ready queue
once backfill finishes.

Change-Id: I171080e683087e3e6f10f43b599778a03cba0a87
Move stream class to its own source/header file

Change-Id: I9d865fd8f0129dd216bb843c23128289b79d3f99
Add an ActiveStream class

Change-Id: If884c335131da9f9138e63a2dda15d28fdc9a3b5
Add checkpoint maanger to upr

Change-Id: I4f5d6a49e31e992bd34b2bce5d8089ccbaffb1f4
Remove backfill stuff from the conn map

Change-Id: I6786b0f1397d94b6ed126a7b62afb30eaceae53a