Add maxTargetSdk restriction to unused APIs.

These are APIs that have @UnsupportedAppUsage but for which we don't
have any evidence of them currently being used, so should be safe to remove
from the unsupported list.

Bug: 170729553
Test: Treehugger
Change-Id: I54fce50d3fb9d3ba02eae312c478bac419a46ede
1 file changed