[Security] resolve RequestIgnoreBatteryOptimizations info disclosure

after discussed with kdeus@ we will remove the setResult() from the
dialog action to avoid the caller apps can distinguish the users
interaction behavior, and declared REQUEST_IGNORE_BATTERY_OPTIMIZATIONS
in other applications.

Bug: 195963373
Test: make SettingsRoboTests
Change-Id: Ia2e47c493c206e96b0bc1d9f08735c0f9474c233