Add flag to enable Haptics Customization feature

This flag will be used to hide any new or modified APIs + the changes made to the RingtonePicker. Once the feature is stable and ready to be launched, the flag will be removed.

Bug: 293846645
Test: N/A
Change-Id: Ie4b07265bc6bd0b89af7e2353c08ca34f89115be
2 files changed