Revert "Don't restore notification channel if its sound is unavailable"

This reverts commit 6a5ca92e75738e605090feab3b6f95bf4ff37d84.

Reason for revert: This is affecting notification channels that are using the system sound and is resulting in users losing most of their notification settings

Change-Id: I350cf8190eec6296a597bef38b711900336ddf75
Fixes: 197129198
3 files changed