Fix inaccessible view issue.

When fully expanded, the last item in the ExpandableListView was half
off the screen, making it hard to see what the value was and update it.
Tweaking the layout to ensure the last item is properly visible.

Bug: 158300259
Bug: 189850067
Test: Visual inspection
Change-Id: Ifc60e220276db6ee6d4dea57957b0b52b1934dbe