ozone: evdev: Convert touchpad disable & internal key filter to settings
This applies the "disable internal touchpad" and "filter all internal
keys except whitelisted ones" features non-racily at startup and after
hotplug events.
This is in preparation for fixing crbug.com/457077. Disabling touchpad
in touchview mode and disabling all devices in ReleaseDisplayOwnership
will use the same functionality.
BUG=457077
TEST=Add --ash-enable-touch-view-testing on pixel & hack
EnableMaximizeModeWindowManager() to enable key filtering
regardless of hinge state. Keys filtered except power.
Review URL: https://codereview.chromium.org/
1187053008
Cr-Commit-Position: refs/heads/master@{#335189}