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: Id54271252e1a7e9e3ffdfeba8b4eba742bcdae3c
11 files changed