Remove Battery Settings page battery saver tips

 - Not present Battery saver tips when it's enabled
 - Not redirect Low battery tips to saver tips when saver is enabled
 Screenshots:
   https://screenshot.googleplex.com/4ehKSRs8gM64wfm.png
   https://screenshot.googleplex.com/92pd3q9jnTEXd8o.png
   https://screenshot.googleplex.com/BzLYwTjdi3kH4RF.png
   https://screenshot.googleplex.com/4w9ubmHaajNxB9b.png

Bug: 183079415
Test: make RunSettingsRoboTests -j40
Change-Id: Ib9783a95df88753342ff217b1a402f2dbb99079d