Set usage graph LTR layout direction for Persian & Urdu

Persian & Urdu are RTL lanuages but users request LTR
usage graph layout direction.

Bug: 153483998
Test: manual visual
      Set locale Persian or Urdu.
      In 'Wi-Fi data usage', the usage graph should be LTR.
Change-Id: I850baa17d12ac3e0de62382fcb90eda9a19dbcbd