Cleanup flag for notification sound Uri permission check Needed for the security bulletin. Flag: EXEMPT security fix Test: atest PreferencesHelperTest Test: atest NotificationManagerServiceTest Bug: 337775777 (cherry picked from https://googleplex-android-review.googlesource.com/q/commit:a6e1ff31bb807aa7aa0d4251f779429441b55ea3) (cherry picked from https://googleplex-android-review.googlesource.com/q/commit:118249b961e979fe4a571a1b41e064327a164f46) Merged-In: If206fb7cfc832f66f0e677c687537062ad0d7043 Change-Id: If206fb7cfc832f66f0e677c687537062ad0d7043