GitLab

This change implements the SetNextUnsubscribeFromNotifications function
for fake characteristics.

BUG=569709

Change-Id: I99c59a4caffd524e727921fcb54f48cc868d545f
Reviewed-on: https://chromium-review.googlesource.com/988223
Commit-Queue: Ovidio Henriquez <odejesush@chromium.org>
Reviewed-by: Oliver Chang <ochang@chromium.org>
Reviewed-by: Giovanni Ortuño Urquidi <ortuno@chromium.org>
Cr-Commit-Position: refs/heads/master@{#548544}