Check against SDK now that it's updated

The platform has moved up its SDK version, so we can replace a few code
instances with an SDK check now. We also use SdkLevel.isAtLeastS() in
places where it was not already in use (this API has already been
updated to use the updated S SDK value)

Bug: 184097792
Test: builds
Change-Id: Idb222826389e4a606733f1a309c9436e96d6186d
2 files changed