Track WinRT device connection status

Windows sometimes sends OnConnectionStatusChange events when the status
has not changed. Previously we had assumed the status changed and acted
accordingly.  This change keeps track of the connection status and if
OnConnctionStatusChange fires with the same status it is now ignored.

Bug: 127810
Change-Id: I64c5b3d99e0ac827f05ca1618d570ff83296a053
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1939827
Reviewed-by: Ovidio de Jesús Ruiz-Henríquez <odejesush@chromium.org>
Commit-Queue: James Hollyer <jameshollyer@chromium.org>
Cr-Commit-Position: refs/heads/master@{#720876}
8 files changed