screenshot: https://screenshot.googleplex.com/A4yihXmkTTo2nM3.png Add seperate controllers in page and guard with flag. Original controller will be disabled if flag is off. This is part of feature for keyboard setting update. document: go/new-a11y-touchpad-mouse-page Bug: 377602364 Test: atest SettingsRoboTests Flag: com.android.settings.keyboard.keyboard_and_touchpad_a11y_new_page_enabled Change-Id: I20bf7c65a7f9adc734c7382f23a92d1eb41822f1