Fix disable/force stop app button incorrect state.

The LayoutPreference calls super.onBindPreview, which enables all
children views. This is usually fine because a Preference object has
just one click target. But the LayoutPreference can hold multiple click
targets so we should not force enable everything during every single
bind.

To fix this, we don't call super.onBind, and manually wire up
onClickListener and selectable/focusable state. Everything else from
super.onBind is useless to this preference type.

Change-Id: Ibb89f1be399311b9ee053733a050f04be6aa85e8
Fix: 37452204
Fix: 37538936
Fix: 35633637
Test: make RunSettingsRoboTests