getActiveNetworkInfo() and friends already know how to augment their
results to help apps detect when network access is blocked. This
change wires up the new app-idle and device-idle firewall rules to
be reported through these APIs.
This also causes other platform tools like DownloadManager and
SyncManager to respect these new policies.
Bug: 24050462
Change-Id: Id9517b0b70be7e3ca2ab27bed8049db916e4d829