[2/n] Camera Compat: Add DeviceConfig flag

Also, refactor boolean setters to reduce code duplication in WindowManagerShellCommand.

Test: manual with adb shell device_config put window_manager enable_camera_compat_treatment true
Bug: 218352945
Change-Id: Ieb01afa8a1941d9a5a5979139d886592122fcd7a
5 files changed