Prevent recent and right navbar icon overlap

Fixes right navbar icon inset into recents button. The inset
reduced the tap target size and Talkback would highlight only
the non-inset part of the icon. Expand the right navbar icons
to use all the space alloted by weight to increase their tap
target.

Change-Id: I5261794c4f6e0dd29f3098e7298455be1b5c520c
Fixes: 66983038
Test: manual