Fix refresh in Gestures, not reflecting the changes after

toggling on/off one-handed mode

1) Remove disabling on swipe down notification.
2) Update to align asset with One-Handed mode temporarily.
3) Change some states when toggle on/off and align with
One-Handed mode.
4) Set temporary asset style to "centerInside" to avoid image
corrupted problem when device rotate.
5) Add new string on Swipe down notification toggle switch.

Bug: 177679988
Bug: 181970213

Test: manual verified on Settings > System > Gesture page
Test: make RunSettingsRoboTests ROBOTEST_FILTER=
      "com.android.settings.gestures.OneHandedSettingsTest"
Test: make RunSettingsRoboTests ROBOTEST_FILTER=
      "com.android.settings.gestures
      .OneHandedAppTapsExitPreferenceControllerTest"
Test: make RunSettingsRoboTests ROBOTEST_FILTER=
      "com.android.settings.gestures
      .OneHandedEnablePreferenceControllerTest"
Test: make RunSettingsRoboTests ROBOTEST_FILTER=
      "com.android.settings.gestures
      .OneHandedTimeoutPreferenceControllerTest"
Test: make RunSettingsRoboTests ROBOTEST_FILTER=
      "com.android.settings.gestures.OneHandedSettingsUtilsTest"
Test: make RunSettingsRoboTests ROBOTEST_FILTER=
      "com.android.settings.gestures.SwipeBottomToNotificationPreferenceControllerTest"
Test: make RunSettingsRoboTests ROBOTEST_FILTER=
      "com.android.settings.gestures.SwipeBottomToNotificationSettingsTest"

Change-Id: Ifd2346a7694323d21eb424891987c8317847e7c5