Overlay navigation_bar_gesture_height with highest order

1) One handed mode will overlay navigation_bar_gesture_height
2) RRO priority attribute only design for static overlay packages
3) Use setHighestPriority() bring OneHandedModeGesturalOverlay to top
4) Integrate 2Button & 3Button mode with values-land dimen

   Mode     | Orientation | Before | After
--------------------------------------------
  NO_BUTTON |  Portrait   |  32dp  |  32dp
  NO_BUTTON |  Landscape  |  32dp  |  32dp
  2 BUTTON  |  Portrait   |  48dp  |  48dp
  2 BUTTON  |  Landscape  |  48dp  |  48dp
  3 BUTTON  |  Portrait   |  48dp  |  48dp
  3 BUTTON  |  Landscape  |  48dp  |  48dp
--------------------------------------------
  OneHanded |  Portrait   |  32dp  | *80dp
  OneHanded |  Landscape  |  32dp  |  32dp

Test: atest WindowInsetsBehaviorTests
Test: atest com.android.systemui.onehanded
Bug: 157958539
Change-Id: I956c90a436dbdc86ca3fb23354cb3a82394ed718