Fix logging spam in DashboardFragment.

When updating preferences managed through PreferenceController, the
fragment should skip prefs that are not available.

Bug: 32255863
Test: RunSettingsRoboTests
Change-Id: I2f9b6ddf8c78d40068dc18f07e60672dcba4474a

src/com/android/settings/display/LiftToWakePreferenceController.java

@@ -34,7 +34,7 @@ public class LiftToWakePreferenceController extends PreferenceController impleme
     }
 
     @Override
-    protected boolean isAvailable() {
+    public boolean isAvailable() {
         SensorManager sensors = (SensorManager) mContext.getSystemService(Context.SENSOR_SERVICE);
         return sensors != null && sensors.getDefaultSensor(Sensor.TYPE_WAKE_GESTURE) != null;
     }