Add some metrics to the initialization of the WMI Refresher.

This will help us understand which part of the initialization are slow
and what the worst cases are. The more granular metrics have been added
to a new "Memory.Experimental.WMIRefresher.Init" namespace.

Bug: 939092
Change-Id: I736ade40068b6717be41890f399560ab68a42a7f
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1508774
Reviewed-by: Brian White <bcwhite@chromium.org>
Reviewed-by: Etienne Bergeron <etienneb@chromium.org>
Commit-Queue: Sébastien Marchand <sebmarchand@chromium.org>
Cr-Commit-Position: refs/heads/master@{#639021}
2 files changed