Limit the number of concurrently snoozed notifications am: bc808de2f8

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/19205942

Change-Id: I3e18ebaacd69e02859eef7812a4b845fa24b93ef
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>