Fix SystemUI navigation bar in RTL mode

In LTR mode the navigation bar is:

- portrait (from left to right) : Back | Home | Recent Apps | Menu
- landscape (from top to bottom) : Menu | Back | Home | Recent Apps

This is kinda horizontally / vertically "pivoting +90 degrees" around the Recent Apps button.

In RTL mode, we had:

- portrait: Menu | Recent Apps | Home | Back
- landscape: Menu | Recent Apps | Home | Back

to make it similar to the LTR mode, we should have a rotation of -90 degrees around the Recent Apps button:

- landscape: Menu | Back | Home | Recent Apps

Change-Id: I9de511383b632ae8dea1396e9152109cc8a57c27