Fix the Int value to reflect shared preferences value in TouchInteractionService.

This cl fixes following things

- When featureFlag is present, always read the value from FeatureFlag.get() instead of preferences.

- Add new function getIntFlagBackedUpByLauncherPrefs to read from sharedPreferences

- Make FlagTogglerPrefUi.java updateMenu() public

- When intFlag is modified in Developer Options, Apply button will show up. So launcher can restart and values get applied.

- Omnient Int flags will read from Featureflag.get() instead of shared preferences directly.

Bug: 320696242
Test: Manual
Flag: NA. Developer Options related

Change-Id: Id916b25d0397505d240ea8444d896c8ace826e57